diff --git a/tests/fixtures/typescript/basics/non-null-assertion-operator.result.js b/tests/fixtures/typescript/basics/non-null-assertion-operator.result.js
new file mode 100644
index 0000000..6a4746e
--- /dev/null
+++ b/tests/fixtures/typescript/basics/non-null-assertion-operator.result.js
@@ -0,0 +1,711 @@
+module.exports = {
+    "type": "Program",
+    "range": [
+        0,
+        82
+    ],
+    "loc": {
+        "start": {
+            "line": 1,
+            "column": 0
+        },
+        "end": {
+            "line": 4,
+            "column": 1
+        }
+    },
+    "body": [
+        {
+            "type": "FunctionDeclaration",
+            "range": [
+                0,
+                82
+            ],
+            "loc": {
+                "start": {
+                    "line": 1,
+                    "column": 0
+                },
+                "end": {
+                    "line": 4,
+                    "column": 1
+                }
+            },
+            "id": {
+                "type": "Identifier",
+                "range": [
+                    9,
+                    22
+                ],
+                "loc": {
+                    "start": {
+                        "line": 1,
+                        "column": 9
+                    },
+                    "end": {
+                        "line": 1,
+                        "column": 22
+                    }
+                },
+                "name": "processEntity"
+            },
+            "generator": false,
+            "expression": false,
+            "params": [
+                {
+                    "type": "Identifier",
+                    "range": [
+                        23,
+                        24
+                    ],
+                    "loc": {
+                        "start": {
+                            "line": 1,
+                            "column": 23
+                        },
+                        "end": {
+                            "line": 1,
+                            "column": 24
+                        }
+                    },
+                    "name": "e"
+                }
+            ],
+            "body": {
+                "type": "BlockStatement",
+                "range": [
+                    35,
+                    82
+                ],
+                "loc": {
+                    "start": {
+                        "line": 1,
+                        "column": 35
+                    },
+                    "end": {
+                        "line": 4,
+                        "column": 1
+                    }
+                },
+                "body": [
+                    {
+                        "type": "ExpressionStatement",
+                        "range": [
+                            41,
+                            59
+                        ],
+                        "loc": {
+                            "start": {
+                                "line": 2,
+                                "column": 4
+                            },
+                            "end": {
+                                "line": 2,
+                                "column": 22
+                            }
+                        },
+                        "expression": {
+                            "type": "CallExpression",
+                            "range": [
+                                41,
+                                58
+                            ],
+                            "loc": {
+                                "start": {
+                                    "line": 2,
+                                    "column": 4
+                                },
+                                "end": {
+                                    "line": 2,
+                                    "column": 21
+                                }
+                            },
+                            "callee": {
+                                "type": "Identifier",
+                                "range": [
+                                    41,
+                                    55
+                                ],
+                                "loc": {
+                                    "start": {
+                                        "line": 2,
+                                        "column": 4
+                                    },
+                                    "end": {
+                                        "line": 2,
+                                        "column": 18
+                                    }
+                                },
+                                "name": "validateEntity"
+                            },
+                            "arguments": [
+                                {
+                                    "type": "Identifier",
+                                    "range": [
+                                        56,
+                                        57
+                                    ],
+                                    "loc": {
+                                        "start": {
+                                            "line": 2,
+                                            "column": 19
+                                        },
+                                        "end": {
+                                            "line": 2,
+                                            "column": 20
+                                        }
+                                    },
+                                    "name": "e"
+                                }
+                            ]
+                        }
+                    },
+                    {
+                        "type": "VariableDeclaration",
+                        "range": [
+                            64,
+                            80
+                        ],
+                        "loc": {
+                            "start": {
+                                "line": 3,
+                                "column": 4
+                            },
+                            "end": {
+                                "line": 3,
+                                "column": 20
+                            }
+                        },
+                        "declarations": [
+                            {
+                                "type": "VariableDeclarator",
+                                "range": [
+                                    68,
+                                    79
+                                ],
+                                "loc": {
+                                    "start": {
+                                        "line": 3,
+                                        "column": 8
+                                    },
+                                    "end": {
+                                        "line": 3,
+                                        "column": 19
+                                    }
+                                },
+                                "id": {
+                                    "type": "Identifier",
+                                    "range": [
+                                        68,
+                                        69
+                                    ],
+                                    "loc": {
+                                        "start": {
+                                            "line": 3,
+                                            "column": 8
+                                        },
+                                        "end": {
+                                            "line": 3,
+                                            "column": 9
+                                        }
+                                    },
+                                    "name": "s"
+                                },
+                                "init": {
+                                    "type": "MemberExpression",
+                                    "range": [
+                                        72,
+                                        79
+                                    ],
+                                    "loc": {
+                                        "start": {
+                                            "line": 3,
+                                            "column": 12
+                                        },
+                                        "end": {
+                                            "line": 3,
+                                            "column": 19
+                                        }
+                                    },
+                                    "object": {
+                                        "type": "TSNonNullExpression",
+                                        "range": [
+                                            72,
+                                            74
+                                        ],
+                                        "loc": {
+                                            "start": {
+                                                "line": 3,
+                                                "column": 12
+                                            },
+                                            "end": {
+                                                "line": 3,
+                                                "column": 14
+                                            }
+                                        },
+                                        "flags": 0,
+                                        "expression": {
+                                            "type": "Identifier",
+                                            "range": [
+                                                72,
+                                                73
+                                            ],
+                                            "loc": {
+                                                "start": {
+                                                    "line": 3,
+                                                    "column": 12
+                                                },
+                                                "end": {
+                                                    "line": 3,
+                                                    "column": 13
+                                                }
+                                            },
+                                            "name": "e"
+                                        }
+                                    },
+                                    "property": {
+                                        "type": "Identifier",
+                                        "range": [
+                                            75,
+                                            79
+                                        ],
+                                        "loc": {
+                                            "start": {
+                                                "line": 3,
+                                                "column": 15
+                                            },
+                                            "end": {
+                                                "line": 3,
+                                                "column": 19
+                                            }
+                                        },
+                                        "name": "name"
+                                    },
+                                    "computed": false
+                                }
+                            }
+                        ],
+                        "kind": "let"
+                    }
+                ]
+            }
+        }
+    ],
+    "sourceType": "script",
+    "tokens": [
+        {
+            "type": "Keyword",
+            "value": "function",
+            "range": [
+                0,
+                8
+            ],
+            "loc": {
+                "start": {
+                    "line": 1,
+                    "column": 0
+                },
+                "end": {
+                    "line": 1,
+                    "column": 8
+                }
+            }
+        },
+        {
+            "type": "Identifier",
+            "value": "processEntity",
+            "range": [
+                9,
+                22
+            ],
+            "loc": {
+                "start": {
+                    "line": 1,
+                    "column": 9
+                },
+                "end": {
+                    "line": 1,
+                    "column": 22
+                }
+            }
+        },
+        {
+            "type": "Punctuator",
+            "value": "(",
+            "range": [
+                22,
+                23
+            ],
+            "loc": {
+                "start": {
+                    "line": 1,
+                    "column": 22
+                },
+                "end": {
+                    "line": 1,
+                    "column": 23
+                }
+            }
+        },
+        {
+            "type": "Identifier",
+            "value": "e",
+            "range": [
+                23,
+                24
+            ],
+            "loc": {
+                "start": {
+                    "line": 1,
+                    "column": 23
+                },
+                "end": {
+                    "line": 1,
+                    "column": 24
+                }
+            }
+        },
+        {
+            "type": "Punctuator",
+            "value": "?",
+            "range": [
+                24,
+                25
+            ],
+            "loc": {
+                "start": {
+                    "line": 1,
+                    "column": 24
+                },
+                "end": {
+                    "line": 1,
+                    "column": 25
+                }
+            }
+        },
+        {
+            "type": "Punctuator",
+            "value": ":",
+            "range": [
+                25,
+                26
+            ],
+            "loc": {
+                "start": {
+                    "line": 1,
+                    "column": 25
+                },
+                "end": {
+                    "line": 1,
+                    "column": 26
+                }
+            }
+        },
+        {
+            "type": "Identifier",
+            "value": "Entity",
+            "range": [
+                27,
+                33
+            ],
+            "loc": {
+                "start": {
+                    "line": 1,
+                    "column": 27
+                },
+                "end": {
+                    "line": 1,
+                    "column": 33
+                }
+            }
+        },
+        {
+            "type": "Punctuator",
+            "value": ")",
+            "range": [
+                33,
+                34
+            ],
+            "loc": {
+                "start": {
+                    "line": 1,
+                    "column": 33
+                },
+                "end": {
+                    "line": 1,
+                    "column": 34
+                }
+            }
+        },
+        {
+            "type": "Punctuator",
+            "value": "{",
+            "range": [
+                35,
+                36
+            ],
+            "loc": {
+                "start": {
+                    "line": 1,
+                    "column": 35
+                },
+                "end": {
+                    "line": 1,
+                    "column": 36
+                }
+            }
+        },
+        {
+            "type": "Identifier",
+            "value": "validateEntity",
+            "range": [
+                41,
+                55
+            ],
+            "loc": {
+                "start": {
+                    "line": 2,
+                    "column": 4
+                },
+                "end": {
+                    "line": 2,
+                    "column": 18
+                }
+            }
+        },
+        {
+            "type": "Punctuator",
+            "value": "(",
+            "range": [
+                55,
+                56
+            ],
+            "loc": {
+                "start": {
+                    "line": 2,
+                    "column": 18
+                },
+                "end": {
+                    "line": 2,
+                    "column": 19
+                }
+            }
+        },
+        {
+            "type": "Identifier",
+            "value": "e",
+            "range": [
+                56,
+                57
+            ],
+            "loc": {
+                "start": {
+                    "line": 2,
+                    "column": 19
+                },
+                "end": {
+                    "line": 2,
+                    "column": 20
+                }
+            }
+        },
+        {
+            "type": "Punctuator",
+            "value": ")",
+            "range": [
+                57,
+                58
+            ],
+            "loc": {
+                "start": {
+                    "line": 2,
+                    "column": 20
+                },
+                "end": {
+                    "line": 2,
+                    "column": 21
+                }
+            }
+        },
+        {
+            "type": "Punctuator",
+            "value": ";",
+            "range": [
+                58,
+                59
+            ],
+            "loc": {
+                "start": {
+                    "line": 2,
+                    "column": 21
+                },
+                "end": {
+                    "line": 2,
+                    "column": 22
+                }
+            }
+        },
+        {
+            "type": "Keyword",
+            "value": "let",
+            "range": [
+                64,
+                67
+            ],
+            "loc": {
+                "start": {
+                    "line": 3,
+                    "column": 4
+                },
+                "end": {
+                    "line": 3,
+                    "column": 7
+                }
+            }
+        },
+        {
+            "type": "Identifier",
+            "value": "s",
+            "range": [
+                68,
+                69
+            ],
+            "loc": {
+                "start": {
+                    "line": 3,
+                    "column": 8
+                },
+                "end": {
+                    "line": 3,
+                    "column": 9
+                }
+            }
+        },
+        {
+            "type": "Punctuator",
+            "value": "=",
+            "range": [
+                70,
+                71
+            ],
+            "loc": {
+                "start": {
+                    "line": 3,
+                    "column": 10
+                },
+                "end": {
+                    "line": 3,
+                    "column": 11
+                }
+            }
+        },
+        {
+            "type": "Identifier",
+            "value": "e",
+            "range": [
+                72,
+                73
+            ],
+            "loc": {
+                "start": {
+                    "line": 3,
+                    "column": 12
+                },
+                "end": {
+                    "line": 3,
+                    "column": 13
+                }
+            }
+        },
+        {
+            "type": "Punctuator",
+            "value": "!",
+            "range": [
+                73,
+                74
+            ],
+            "loc": {
+                "start": {
+                    "line": 3,
+                    "column": 13
+                },
+                "end": {
+                    "line": 3,
+                    "column": 14
+                }
+            }
+        },
+        {
+            "type": "Punctuator",
+            "value": ".",
+            "range": [
+                74,
+                75
+            ],
+            "loc": {
+                "start": {
+                    "line": 3,
+                    "column": 14
+                },
+                "end": {
+                    "line": 3,
+                    "column": 15
+                }
+            }
+        },
+        {
+            "type": "Identifier",
+            "value": "name",
+            "range": [
+                75,
+                79
+            ],
+            "loc": {
+                "start": {
+                    "line": 3,
+                    "column": 15
+                },
+                "end": {
+                    "line": 3,
+                    "column": 19
+                }
+            }
+        },
+        {
+            "type": "Punctuator",
+            "value": ";",
+            "range": [
+                79,
+                80
+            ],
+            "loc": {
+                "start": {
+                    "line": 3,
+                    "column": 19
+                },
+                "end": {
+                    "line": 3,
+                    "column": 20
+                }
+            }
+        },
+        {
+            "type": "Punctuator",
+            "value": "}",
+            "range": [
+                81,
+                82
+            ],
+            "loc": {
+                "start": {
+                    "line": 4,
+                    "column": 0
+                },
+                "end": {
+                    "line": 4,
+                    "column": 1
+                }
+            }
+        }
+    ]
+};
diff --git a/tests/fixtures/typescript/basics/non-null-assertion-operator.src.ts b/tests/fixtures/typescript/basics/non-null-assertion-operator.src.ts
new file mode 100644
index 0000000..18e7385
--- /dev/null
+++ b/tests/fixtures/typescript/basics/non-null-assertion-operator.src.ts
@@ -0,0 +1,4 @@
+function processEntity(e?: Entity) {
+    validateEntity(e);
+    let s = e!.name;
+}
\ No newline at end of file