diff --git a/lib/ast-converter.js b/lib/ast-converter.js
index ea8a187..8b009ca 100644
--- a/lib/ast-converter.js
+++ b/lib/ast-converter.js
@@ -759,6 +759,7 @@ module.exports = function(ast, extra) {
                     SyntaxKind.Parameter === node.parent.kind ||
                     SyntaxKind.PropertyDeclaration === node.parent.kind ||
                     SyntaxKind.PropertySignature === node.parent.kind ||
+                    SyntaxKind.MethodDeclaration === node.parent.kind ||
                     SyntaxKind.MethodSignature === node.parent.kind
                 )) {
                     result.optional = true;
diff --git a/tests/fixtures/typescript/basics/abstract-class-with-optional-method.result.js b/tests/fixtures/typescript/basics/abstract-class-with-optional-method.result.js
new file mode 100644
index 0000000..9e409d8
--- /dev/null
+++ b/tests/fixtures/typescript/basics/abstract-class-with-optional-method.result.js
@@ -0,0 +1,521 @@
+module.exports = {
+    "body": [
+        {
+            "declaration": {
+                "body": {
+                    "body": [
+                        {
+                            "accessibility": null,
+                            "computed": false,
+                            "decorators": [],
+                            "key": {
+                                "loc": {
+                                    "end": {
+                                        "column": 16,
+                                        "line": 2
+                                    },
+                                    "start": {
+                                        "column": 4,
+                                        "line": 2
+                                    }
+                                },
+                                "name": "createSocket",
+                                "optional": true,
+                                "range": [
+                                    43,
+                                    55
+                                ],
+                                "type": "Identifier"
+                            },
+                            "kind": "method",
+                            "loc": {
+                                "end": {
+                                    "column": 37,
+                                    "line": 2
+                                },
+                                "start": {
+                                    "column": 4,
+                                    "line": 2
+                                }
+                            },
+                            "range": [
+                                43,
+                                76
+                            ],
+                            "static": false,
+                            "type": "MethodDefinition",
+                            "value": {
+                                "async": false,
+                                "body": null,
+                                "expression": false,
+                                "generator": false,
+                                "id": null,
+                                "loc": {
+                                    "end": {
+                                        "column": 37,
+                                        "line": 2
+                                    },
+                                    "start": {
+                                        "column": 16,
+                                        "line": 2
+                                    }
+                                },
+                                "params": [],
+                                "range": [
+                                    56,
+                                    76
+                                ],
+                                "returnType": {
+                                    "loc": {
+                                        "end": {
+                                            "column": 36,
+                                            "line": 2
+                                        },
+                                        "start": {
+                                            "column": 21,
+                                            "line": 2
+                                        }
+                                    },
+                                    "range": [
+                                        60,
+                                        75
+                                    ],
+                                    "type": "TypeAnnotation",
+                                    "typeAnnotation": {
+                                        "loc": {
+                                            "end": {
+                                                "column": 36,
+                                                "line": 2
+                                            },
+                                            "start": {
+                                                "column": 21,
+                                                "line": 2
+                                            }
+                                        },
+                                        "range": [
+                                            60,
+                                            75
+                                        ],
+                                        "type": "TSTypeReference",
+                                        "typeArguments": [
+                                            {
+                                                "loc": {
+                                                    "end": {
+                                                        "column": 35,
+                                                        "line": 2
+                                                    },
+                                                    "start": {
+                                                        "column": 29,
+                                                        "line": 2
+                                                    }
+                                                },
+                                                "range": [
+                                                    68,
+                                                    74
+                                                ],
+                                                "type": "TSStringKeyword"
+                                            }
+                                        ],
+                                        "typeName": {
+                                            "loc": {
+                                                "end": {
+                                                    "column": 28,
+                                                    "line": 2
+                                                },
+                                                "start": {
+                                                    "column": 21,
+                                                    "line": 2
+                                                }
+                                            },
+                                            "name": "Promise",
+                                            "range": [
+                                                60,
+                                                67
+                                            ],
+                                            "type": "Identifier"
+                                        }
+                                    }
+                                },
+                                "type": "FunctionExpression"
+                            }
+                        }
+                    ],
+                    "loc": {
+                        "end": {
+                            "column": 1,
+                            "line": 3
+                        },
+                        "start": {
+                            "column": 37,
+                            "line": 1
+                        }
+                    },
+                    "range": [
+                        37,
+                        78
+                    ],
+                    "type": "ClassBody"
+                },
+                "decorators": [],
+                "id": {
+                    "loc": {
+                        "end": {
+                            "column": 36,
+                            "line": 1
+                        },
+                        "start": {
+                            "column": 22,
+                            "line": 1
+                        }
+                    },
+                    "name": "AbstractSocket",
+                    "range": [
+                        22,
+                        36
+                    ],
+                    "type": "Identifier"
+                },
+                "implements": [],
+                "loc": {
+                    "end": {
+                        "column": 1,
+                        "line": 3
+                    },
+                    "start": {
+                        "column": 16,
+                        "line": 1
+                    }
+                },
+                "range": [
+                    16,
+                    78
+                ],
+                "superClass": null,
+                "type": "TSAbstractClassDeclaration"
+            },
+            "loc": {
+                "end": {
+                    "column": 1,
+                    "line": 3
+                },
+                "start": {
+                    "column": 0,
+                    "line": 1
+                }
+            },
+            "range": [
+                0,
+                78
+            ],
+            "source": null,
+            "specifiers": [],
+            "type": "ExportNamedDeclaration"
+        }
+    ],
+    "loc": {
+        "end": {
+            "column": 1,
+            "line": 3
+        },
+        "start": {
+            "column": 0,
+            "line": 1
+        }
+    },
+    "range": [
+        0,
+        78
+    ],
+    "sourceType": "module",
+    "tokens": [
+        {
+            "loc": {
+                "end": {
+                    "column": 6,
+                    "line": 1
+                },
+                "start": {
+                    "column": 0,
+                    "line": 1
+                }
+            },
+            "range": [
+                0,
+                6
+            ],
+            "type": "Keyword",
+            "value": "export"
+        },
+        {
+            "loc": {
+                "end": {
+                    "column": 15,
+                    "line": 1
+                },
+                "start": {
+                    "column": 7,
+                    "line": 1
+                }
+            },
+            "range": [
+                7,
+                15
+            ],
+            "type": "Identifier",
+            "value": "abstract"
+        },
+        {
+            "loc": {
+                "end": {
+                    "column": 21,
+                    "line": 1
+                },
+                "start": {
+                    "column": 16,
+                    "line": 1
+                }
+            },
+            "range": [
+                16,
+                21
+            ],
+            "type": "Keyword",
+            "value": "class"
+        },
+        {
+            "loc": {
+                "end": {
+                    "column": 36,
+                    "line": 1
+                },
+                "start": {
+                    "column": 22,
+                    "line": 1
+                }
+            },
+            "range": [
+                22,
+                36
+            ],
+            "type": "Identifier",
+            "value": "AbstractSocket"
+        },
+        {
+            "loc": {
+                "end": {
+                    "column": 38,
+                    "line": 1
+                },
+                "start": {
+                    "column": 37,
+                    "line": 1
+                }
+            },
+            "range": [
+                37,
+                38
+            ],
+            "type": "Punctuator",
+            "value": "{"
+        },
+        {
+            "loc": {
+                "end": {
+                    "column": 16,
+                    "line": 2
+                },
+                "start": {
+                    "column": 4,
+                    "line": 2
+                }
+            },
+            "range": [
+                43,
+                55
+            ],
+            "type": "Identifier",
+            "value": "createSocket"
+        },
+        {
+            "loc": {
+                "end": {
+                    "column": 17,
+                    "line": 2
+                },
+                "start": {
+                    "column": 16,
+                    "line": 2
+                }
+            },
+            "range": [
+                55,
+                56
+            ],
+            "type": "Punctuator",
+            "value": "?"
+        },
+        {
+            "loc": {
+                "end": {
+                    "column": 18,
+                    "line": 2
+                },
+                "start": {
+                    "column": 17,
+                    "line": 2
+                }
+            },
+            "range": [
+                56,
+                57
+            ],
+            "type": "Punctuator",
+            "value": "("
+        },
+        {
+            "loc": {
+                "end": {
+                    "column": 19,
+                    "line": 2
+                },
+                "start": {
+                    "column": 18,
+                    "line": 2
+                }
+            },
+            "range": [
+                57,
+                58
+            ],
+            "type": "Punctuator",
+            "value": ")"
+        },
+        {
+            "loc": {
+                "end": {
+                    "column": 20,
+                    "line": 2
+                },
+                "start": {
+                    "column": 19,
+                    "line": 2
+                }
+            },
+            "range": [
+                58,
+                59
+            ],
+            "type": "Punctuator",
+            "value": ":"
+        },
+        {
+            "loc": {
+                "end": {
+                    "column": 28,
+                    "line": 2
+                },
+                "start": {
+                    "column": 21,
+                    "line": 2
+                }
+            },
+            "range": [
+                60,
+                67
+            ],
+            "type": "Identifier",
+            "value": "Promise"
+        },
+        {
+            "loc": {
+                "end": {
+                    "column": 29,
+                    "line": 2
+                },
+                "start": {
+                    "column": 28,
+                    "line": 2
+                }
+            },
+            "range": [
+                67,
+                68
+            ],
+            "type": "Punctuator",
+            "value": "<"
+        },
+        {
+            "loc": {
+                "end": {
+                    "column": 35,
+                    "line": 2
+                },
+                "start": {
+                    "column": 29,
+                    "line": 2
+                }
+            },
+            "range": [
+                68,
+                74
+            ],
+            "type": "Identifier",
+            "value": "string"
+        },
+        {
+            "loc": {
+                "end": {
+                    "column": 36,
+                    "line": 2
+                },
+                "start": {
+                    "column": 35,
+                    "line": 2
+                }
+            },
+            "range": [
+                74,
+                75
+            ],
+            "type": "Punctuator",
+            "value": ">"
+        },
+        {
+            "loc": {
+                "end": {
+                    "column": 37,
+                    "line": 2
+                },
+                "start": {
+                    "column": 36,
+                    "line": 2
+                }
+            },
+            "range": [
+                75,
+                76
+            ],
+            "type": "Punctuator",
+            "value": ";"
+        },
+        {
+            "loc": {
+                "end": {
+                    "column": 1,
+                    "line": 3
+                },
+                "start": {
+                    "column": 0,
+                    "line": 3
+                }
+            },
+            "range": [
+                77,
+                78
+            ],
+            "type": "Punctuator",
+            "value": "}"
+        }
+    ],
+    "type": "Program"
+};
diff --git a/tests/fixtures/typescript/basics/abstract-class-with-optional-method.src.ts b/tests/fixtures/typescript/basics/abstract-class-with-optional-method.src.ts
new file mode 100644
index 0000000..f39ba3f
--- /dev/null
+++ b/tests/fixtures/typescript/basics/abstract-class-with-optional-method.src.ts
@@ -0,0 +1,3 @@
+export abstract class AbstractSocket {
+    createSocket?(): Promise<string>;
+}
\ No newline at end of file
diff --git a/tests/fixtures/typescript/basics/class-with-optional-methods.result.js b/tests/fixtures/typescript/basics/class-with-optional-methods.result.js
new file mode 100644
index 0000000..13b27ea
--- /dev/null
+++ b/tests/fixtures/typescript/basics/class-with-optional-methods.result.js
@@ -0,0 +1,771 @@
+module.exports = {
+    "body": [
+        {
+            "body": {
+                "body": [
+                    {
+                        "accessibility": null,
+                        "computed": false,
+                        "decorators": [],
+                        "key": {
+                            "loc": {
+                                "end": {
+                                    "column": 5,
+                                    "line": 2
+                                },
+                                "start": {
+                                    "column": 2,
+                                    "line": 2
+                                }
+                            },
+                            "name": "foo",
+                            "optional": true,
+                            "range": [
+                                14,
+                                17
+                            ],
+                            "type": "Identifier"
+                        },
+                        "kind": "method",
+                        "loc": {
+                            "end": {
+                                "column": 9,
+                                "line": 2
+                            },
+                            "start": {
+                                "column": 2,
+                                "line": 2
+                            }
+                        },
+                        "range": [
+                            14,
+                            21
+                        ],
+                        "static": false,
+                        "type": "MethodDefinition",
+                        "value": {
+                            "async": false,
+                            "body": null,
+                            "expression": false,
+                            "generator": false,
+                            "id": null,
+                            "loc": {
+                                "end": {
+                                    "column": 9,
+                                    "line": 2
+                                },
+                                "start": {
+                                    "column": 5,
+                                    "line": 2
+                                }
+                            },
+                            "params": [],
+                            "range": [
+                                18,
+                                21
+                            ],
+                            "type": "FunctionExpression"
+                        }
+                    },
+                    {
+                        "accessibility": null,
+                        "computed": false,
+                        "decorators": [],
+                        "key": {
+                            "loc": {
+                                "end": {
+                                    "column": 5,
+                                    "line": 3
+                                },
+                                "start": {
+                                    "column": 2,
+                                    "line": 3
+                                }
+                            },
+                            "name": "bar",
+                            "optional": true,
+                            "range": [
+                                24,
+                                27
+                            ],
+                            "type": "Identifier"
+                        },
+                        "kind": "method",
+                        "loc": {
+                            "end": {
+                                "column": 17,
+                                "line": 3
+                            },
+                            "start": {
+                                "column": 2,
+                                "line": 3
+                            }
+                        },
+                        "range": [
+                            24,
+                            39
+                        ],
+                        "static": false,
+                        "type": "MethodDefinition",
+                        "value": {
+                            "async": false,
+                            "body": null,
+                            "expression": false,
+                            "generator": false,
+                            "id": null,
+                            "loc": {
+                                "end": {
+                                    "column": 17,
+                                    "line": 3
+                                },
+                                "start": {
+                                    "column": 5,
+                                    "line": 3
+                                }
+                            },
+                            "params": [],
+                            "range": [
+                                28,
+                                39
+                            ],
+                            "returnType": {
+                                "loc": {
+                                    "end": {
+                                        "column": 16,
+                                        "line": 3
+                                    },
+                                    "start": {
+                                        "column": 10,
+                                        "line": 3
+                                    }
+                                },
+                                "range": [
+                                    32,
+                                    38
+                                ],
+                                "type": "TypeAnnotation",
+                                "typeAnnotation": {
+                                    "loc": {
+                                        "end": {
+                                            "column": 16,
+                                            "line": 3
+                                        },
+                                        "start": {
+                                            "column": 10,
+                                            "line": 3
+                                        }
+                                    },
+                                    "range": [
+                                        32,
+                                        38
+                                    ],
+                                    "type": "TSStringKeyword"
+                                }
+                            },
+                            "type": "FunctionExpression"
+                        }
+                    },
+                    {
+                        "accessibility": "private",
+                        "computed": false,
+                        "decorators": [],
+                        "key": {
+                            "loc": {
+                                "end": {
+                                    "column": 13,
+                                    "line": 4
+                                },
+                                "start": {
+                                    "column": 10,
+                                    "line": 4
+                                }
+                            },
+                            "name": "baz",
+                            "optional": true,
+                            "range": [
+                                50,
+                                53
+                            ],
+                            "type": "Identifier"
+                        },
+                        "kind": "method",
+                        "loc": {
+                            "end": {
+                                "column": 25,
+                                "line": 4
+                            },
+                            "start": {
+                                "column": 2,
+                                "line": 4
+                            }
+                        },
+                        "range": [
+                            42,
+                            65
+                        ],
+                        "static": false,
+                        "type": "MethodDefinition",
+                        "value": {
+                            "async": false,
+                            "body": null,
+                            "expression": false,
+                            "generator": false,
+                            "id": null,
+                            "loc": {
+                                "end": {
+                                    "column": 25,
+                                    "line": 4
+                                },
+                                "start": {
+                                    "column": 13,
+                                    "line": 4
+                                }
+                            },
+                            "params": [],
+                            "range": [
+                                54,
+                                65
+                            ],
+                            "returnType": {
+                                "loc": {
+                                    "end": {
+                                        "column": 24,
+                                        "line": 4
+                                    },
+                                    "start": {
+                                        "column": 18,
+                                        "line": 4
+                                    }
+                                },
+                                "range": [
+                                    58,
+                                    64
+                                ],
+                                "type": "TypeAnnotation",
+                                "typeAnnotation": {
+                                    "loc": {
+                                        "end": {
+                                            "column": 24,
+                                            "line": 4
+                                        },
+                                        "start": {
+                                            "column": 18,
+                                            "line": 4
+                                        }
+                                    },
+                                    "range": [
+                                        58,
+                                        64
+                                    ],
+                                    "type": "TSStringKeyword"
+                                }
+                            },
+                            "type": "FunctionExpression"
+                        }
+                    }
+                ],
+                "loc": {
+                    "end": {
+                        "column": 1,
+                        "line": 5
+                    },
+                    "start": {
+                        "column": 10,
+                        "line": 1
+                    }
+                },
+                "range": [
+                    10,
+                    67
+                ],
+                "type": "ClassBody"
+            },
+            "decorators": [],
+            "id": {
+                "loc": {
+                    "end": {
+                        "column": 9,
+                        "line": 1
+                    },
+                    "start": {
+                        "column": 6,
+                        "line": 1
+                    }
+                },
+                "name": "Foo",
+                "range": [
+                    6,
+                    9
+                ],
+                "type": "Identifier"
+            },
+            "implements": [],
+            "loc": {
+                "end": {
+                    "column": 1,
+                    "line": 5
+                },
+                "start": {
+                    "column": 0,
+                    "line": 1
+                }
+            },
+            "range": [
+                0,
+                67
+            ],
+            "superClass": null,
+            "type": "ClassDeclaration"
+        }
+    ],
+    "loc": {
+        "end": {
+            "column": 1,
+            "line": 5
+        },
+        "start": {
+            "column": 0,
+            "line": 1
+        }
+    },
+    "range": [
+        0,
+        67
+    ],
+    "sourceType": "script",
+    "tokens": [
+        {
+            "loc": {
+                "end": {
+                    "column": 5,
+                    "line": 1
+                },
+                "start": {
+                    "column": 0,
+                    "line": 1
+                }
+            },
+            "range": [
+                0,
+                5
+            ],
+            "type": "Keyword",
+            "value": "class"
+        },
+        {
+            "loc": {
+                "end": {
+                    "column": 9,
+                    "line": 1
+                },
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+                    "column": 6,
+                    "line": 1
+                }
+            },
+            "range": [
+                6,
+                9
+            ],
+            "type": "Identifier",
+            "value": "Foo"
+        },
+        {
+            "loc": {
+                "end": {
+                    "column": 11,
+                    "line": 1
+                },
+                "start": {
+                    "column": 10,
+                    "line": 1
+                }
+            },
+            "range": [
+                10,
+                11
+            ],
+            "type": "Punctuator",
+            "value": "{"
+        },
+        {
+            "loc": {
+                "end": {
+                    "column": 5,
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+                },
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+                    "column": 2,
+                    "line": 2
+                }
+            },
+            "range": [
+                14,
+                17
+            ],
+            "type": "Identifier",
+            "value": "foo"
+        },
+        {
+            "loc": {
+                "end": {
+                    "column": 6,
+                    "line": 2
+                },
+                "start": {
+                    "column": 5,
+                    "line": 2
+                }
+            },
+            "range": [
+                17,
+                18
+            ],
+            "type": "Punctuator",
+            "value": "?"
+        },
+        {
+            "loc": {
+                "end": {
+                    "column": 7,
+                    "line": 2
+                },
+                "start": {
+                    "column": 6,
+                    "line": 2
+                }
+            },
+            "range": [
+                18,
+                19
+            ],
+            "type": "Punctuator",
+            "value": "("
+        },
+        {
+            "loc": {
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+                },
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+                }
+            },
+            "range": [
+                19,
+                20
+            ],
+            "type": "Punctuator",
+            "value": ")"
+        },
+        {
+            "loc": {
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+                }
+            },
+            "range": [
+                20,
+                21
+            ],
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+            "value": "bar"
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+                },
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+                }
+            },
+            "range": [
+                27,
+                28
+            ],
+            "type": "Punctuator",
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+                    "line": 3
+                }
+            },
+            "range": [
+                29,
+                30
+            ],
+            "type": "Punctuator",
+            "value": ")"
+        },
+        {
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+                }
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+            "range": [
+                32,
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+            ],
+            "type": "Identifier",
+            "value": "string"
+        },
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+            "loc": {
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+                38,
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+            ],
+            "type": "Punctuator",
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+        },
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+                    "column": 2,
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+            "range": [
+                42,
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+            "type": "Keyword",
+            "value": "private"
+        },
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+                    "line": 4
+                }
+            },
+            "range": [
+                50,
+                53
+            ],
+            "type": "Identifier",
+            "value": "baz"
+        },
+        {
+            "loc": {
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+                    "column": 14,
+                    "line": 4
+                },
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+                    "column": 13,
+                    "line": 4
+                }
+            },
+            "range": [
+                53,
+                54
+            ],
+            "type": "Punctuator",
+            "value": "?"
+        },
+        {
+            "loc": {
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+                    "line": 4
+                },
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+                    "line": 4
+                }
+            },
+            "range": [
+                54,
+                55
+            ],
+            "type": "Punctuator",
+            "value": "("
+        },
+        {
+            "loc": {
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+                },
+                "start": {
+                    "column": 15,
+                    "line": 4
+                }
+            },
+            "range": [
+                55,
+                56
+            ],
+            "type": "Punctuator",
+            "value": ")"
+        },
+        {
+            "loc": {
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+                    "line": 4
+                },
+                "start": {
+                    "column": 16,
+                    "line": 4
+                }
+            },
+            "range": [
+                56,
+                57
+            ],
+            "type": "Punctuator",
+            "value": ":"
+        },
+        {
+            "loc": {
+                "end": {
+                    "column": 24,
+                    "line": 4
+                },
+                "start": {
+                    "column": 18,
+                    "line": 4
+                }
+            },
+            "range": [
+                58,
+                64
+            ],
+            "type": "Identifier",
+            "value": "string"
+        },
+        {
+            "loc": {
+                "end": {
+                    "column": 25,
+                    "line": 4
+                },
+                "start": {
+                    "column": 24,
+                    "line": 4
+                }
+            },
+            "range": [
+                64,
+                65
+            ],
+            "type": "Punctuator",
+            "value": ";"
+        },
+        {
+            "loc": {
+                "end": {
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+                },
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+                    "column": 0,
+                    "line": 5
+                }
+            },
+            "range": [
+                66,
+                67
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+            "type": "Punctuator",
+            "value": "}"
+        }
+    ],
+    "type": "Program"
+};
diff --git a/tests/fixtures/typescript/basics/class-with-optional-methods.src.ts b/tests/fixtures/typescript/basics/class-with-optional-methods.src.ts
new file mode 100644
index 0000000..2fe152d
--- /dev/null
+++ b/tests/fixtures/typescript/basics/class-with-optional-methods.src.ts
@@ -0,0 +1,5 @@
+class Foo {
+  foo?();
+  bar?(): string;
+  private baz?(): string;
+}
diff --git a/tests/fixtures/typescript/basics/declare-class-with-optional-method.result.js b/tests/fixtures/typescript/basics/declare-class-with-optional-method.result.js
new file mode 100644
index 0000000..d834af4
--- /dev/null
+++ b/tests/fixtures/typescript/basics/declare-class-with-optional-method.result.js
@@ -0,0 +1,393 @@
+module.exports = {
+    "body": [
+        {
+            "body": {
+                "body": [
+                    {
+                        "accessibility": null,
+                        "computed": false,
+                        "decorators": [],
+                        "key": {
+                            "loc": {
+                                "end": {
+                                    "column": 7,
+                                    "line": 2
+                                },
+                                "start": {
+                                    "column": 4,
+                                    "line": 2
+                                }
+                            },
+                            "name": "bar",
+                            "optional": true,
+                            "range": [
+                                24,
+                                27
+                            ],
+                            "type": "Identifier"
+                        },
+                        "kind": "method",
+                        "loc": {
+                            "end": {
+                                "column": 16,
+                                "line": 2
+                            },
+                            "start": {
+                                "column": 4,
+                                "line": 2
+                            }
+                        },
+                        "range": [
+                            24,
+                            36
+                        ],
+                        "static": false,
+                        "type": "MethodDefinition",
+                        "value": {
+                            "async": false,
+                            "body": null,
+                            "expression": false,
+                            "generator": false,
+                            "id": null,
+                            "loc": {
+                                "end": {
+                                    "column": 16,
+                                    "line": 2
+                                },
+                                "start": {
+                                    "column": 7,
+                                    "line": 2
+                                }
+                            },
+                            "params": [],
+                            "range": [
+                                28,
+                                36
+                            ],
+                            "returnType": {
+                                "loc": {
+                                    "end": {
+                                        "column": 15,
+                                        "line": 2
+                                    },
+                                    "start": {
+                                        "column": 12,
+                                        "line": 2
+                                    }
+                                },
+                                "range": [
+                                    32,
+                                    35
+                                ],
+                                "type": "TypeAnnotation",
+                                "typeAnnotation": {
+                                    "loc": {
+                                        "end": {
+                                            "column": 15,
+                                            "line": 2
+                                        },
+                                        "start": {
+                                            "column": 12,
+                                            "line": 2
+                                        }
+                                    },
+                                    "range": [
+                                        32,
+                                        35
+                                    ],
+                                    "type": "TSAnyKeyword"
+                                }
+                            },
+                            "type": "FunctionExpression"
+                        }
+                    }
+                ],
+                "loc": {
+                    "end": {
+                        "column": 1,
+                        "line": 3
+                    },
+                    "start": {
+                        "column": 18,
+                        "line": 1
+                    }
+                },
+                "range": [
+                    18,
+                    38
+                ],
+                "type": "ClassBody"
+            },
+            "decorators": [],
+            "id": {
+                "loc": {
+                    "end": {
+                        "column": 17,
+                        "line": 1
+                    },
+                    "start": {
+                        "column": 14,
+                        "line": 1
+                    }
+                },
+                "name": "Foo",
+                "range": [
+                    14,
+                    17
+                ],
+                "type": "Identifier"
+            },
+            "implements": [],
+            "loc": {
+                "end": {
+                    "column": 1,
+                    "line": 3
+                },
+                "start": {
+                    "column": 0,
+                    "line": 1
+                }
+            },
+            "range": [
+                0,
+                38
+            ],
+            "superClass": null,
+            "type": "ClassDeclaration"
+        }
+    ],
+    "loc": {
+        "end": {
+            "column": 1,
+            "line": 3
+        },
+        "start": {
+            "column": 0,
+            "line": 1
+        }
+    },
+    "range": [
+        0,
+        38
+    ],
+    "sourceType": "script",
+    "tokens": [
+        {
+            "loc": {
+                "end": {
+                    "column": 7,
+                    "line": 1
+                },
+                "start": {
+                    "column": 0,
+                    "line": 1
+                }
+            },
+            "range": [
+                0,
+                7
+            ],
+            "type": "Identifier",
+            "value": "declare"
+        },
+        {
+            "loc": {
+                "end": {
+                    "column": 13,
+                    "line": 1
+                },
+                "start": {
+                    "column": 8,
+                    "line": 1
+                }
+            },
+            "range": [
+                8,
+                13
+            ],
+            "type": "Keyword",
+            "value": "class"
+        },
+        {
+            "loc": {
+                "end": {
+                    "column": 17,
+                    "line": 1
+                },
+                "start": {
+                    "column": 14,
+                    "line": 1
+                }
+            },
+            "range": [
+                14,
+                17
+            ],
+            "type": "Identifier",
+            "value": "Foo"
+        },
+        {
+            "loc": {
+                "end": {
+                    "column": 19,
+                    "line": 1
+                },
+                "start": {
+                    "column": 18,
+                    "line": 1
+                }
+            },
+            "range": [
+                18,
+                19
+            ],
+            "type": "Punctuator",
+            "value": "{"
+        },
+        {
+            "loc": {
+                "end": {
+                    "column": 7,
+                    "line": 2
+                },
+                "start": {
+                    "column": 4,
+                    "line": 2
+                }
+            },
+            "range": [
+                24,
+                27
+            ],
+            "type": "Identifier",
+            "value": "bar"
+        },
+        {
+            "loc": {
+                "end": {
+                    "column": 8,
+                    "line": 2
+                },
+                "start": {
+                    "column": 7,
+                    "line": 2
+                }
+            },
+            "range": [
+                27,
+                28
+            ],
+            "type": "Punctuator",
+            "value": "?"
+        },
+        {
+            "loc": {
+                "end": {
+                    "column": 9,
+                    "line": 2
+                },
+                "start": {
+                    "column": 8,
+                    "line": 2
+                }
+            },
+            "range": [
+                28,
+                29
+            ],
+            "type": "Punctuator",
+            "value": "("
+        },
+        {
+            "loc": {
+                "end": {
+                    "column": 10,
+                    "line": 2
+                },
+                "start": {
+                    "column": 9,
+                    "line": 2
+                }
+            },
+            "range": [
+                29,
+                30
+            ],
+            "type": "Punctuator",
+            "value": ")"
+        },
+        {
+            "loc": {
+                "end": {
+                    "column": 11,
+                    "line": 2
+                },
+                "start": {
+                    "column": 10,
+                    "line": 2
+                }
+            },
+            "range": [
+                30,
+                31
+            ],
+            "type": "Punctuator",
+            "value": ":"
+        },
+        {
+            "loc": {
+                "end": {
+                    "column": 15,
+                    "line": 2
+                },
+                "start": {
+                    "column": 12,
+                    "line": 2
+                }
+            },
+            "range": [
+                32,
+                35
+            ],
+            "type": "Identifier",
+            "value": "any"
+        },
+        {
+            "loc": {
+                "end": {
+                    "column": 16,
+                    "line": 2
+                },
+                "start": {
+                    "column": 15,
+                    "line": 2
+                }
+            },
+            "range": [
+                35,
+                36
+            ],
+            "type": "Punctuator",
+            "value": ";"
+        },
+        {
+            "loc": {
+                "end": {
+                    "column": 1,
+                    "line": 3
+                },
+                "start": {
+                    "column": 0,
+                    "line": 3
+                }
+            },
+            "range": [
+                37,
+                38
+            ],
+            "type": "Punctuator",
+            "value": "}"
+        }
+    ],
+    "type": "Program"
+};
diff --git a/tests/fixtures/typescript/basics/declare-class-with-optional-method.src.ts b/tests/fixtures/typescript/basics/declare-class-with-optional-method.src.ts
new file mode 100644
index 0000000..ecb4a4e
--- /dev/null
+++ b/tests/fixtures/typescript/basics/declare-class-with-optional-method.src.ts
@@ -0,0 +1,3 @@
+declare class Foo {
+    bar?(): any;
+}
\ No newline at end of file