support moduleSuffixes in tsconfig.json

Author: evanw

CHANGELOG.md

@@ -1,5 +1,11 @@
 # Changelog
 
+## Unreleased
+
+* Add support for TypeScript's `moduleSuffixes` field from TypeScript 4.7
+
+    The upcoming version of TypeScript adds the `moduleSuffixes` field to `tsconfig.json` that introduces more rules to import path resolution. Setting `moduleSuffixes` to `[".ios", ".native", ""]` will try to look at the the relative files `./foo.ios.ts`, `./foo.native.ts`, and finally `./foo.ts` for an import path of `./foo`. Note that the empty string `""` in `moduleSuffixes` is necessary for TypeScript to also look-up `./foo.ts`. This was announced in the [TypeScript 4.7 beta blog post](https://devblogs.microsoft.com/typescript/announcing-typescript-4-7-beta/#resolution-customization-with-modulesuffixes).
+
 ## 0.14.36
 
 * Revert path metadata validation for now ([#2177](https://github.com/evanw/esbuild/issues/2177))

internal/bundler/bundler_tsconfig_test.go

@@ -1514,3 +1514,98 @@ func TestTsConfigPathsExtendsBaseURL(t *testing.T) {
 		},
 	})
 }
+
+func TestTsConfigModuleSuffixesInsert(t *testing.T) {
+	tsconfig_suite.expectBundled(t, bundled{
+		files: map[string]string{
+			"/Users/user/project/src/entry.ts": `
+				import "./foo"
+				import "./bar.js"
+				import "./baz.a.js"
+			`,
+
+			"/Users/user/project/src/foo.a.ts": `console.log('foo.a')`,
+			"/Users/user/project/src/foo.b.ts": `console.log('foo.b')`,
+			"/Users/user/project/src/foo.ts":   `console.log('foo')`,
+
+			"/Users/user/project/src/bar.a.ts": `console.log('bar.a')`,
+			"/Users/user/project/src/bar.b.ts": `console.log('bar.b')`,
+			"/Users/user/project/src/bar.ts":   `console.log('bar')`,
+
+			"/Users/user/project/src/baz.a.ts": `console.log('baz.a')`,
+			"/Users/user/project/src/baz.b.ts": `console.log('baz.b')`,
+			"/Users/user/project/src/baz.ts":   `console.log('baz')`,
+
+			"/Users/user/project/tsconfig.json": `{
+				"compilerOptions": {
+					"moduleSuffixes": [".a", ".b", ""]
+				}
+			}`,
+		},
+		entryPaths: []string{"/Users/user/project/src/entry.ts"},
+		options: config.Options{
+			Mode:          config.ModeBundle,
+			AbsOutputFile: "/Users/user/project/out.js",
+		},
+	})
+}
+
+func TestTsConfigModuleSuffixesNoInsert(t *testing.T) {
+	tsconfig_suite.expectBundled(t, bundled{
+		files: map[string]string{
+			"/Users/user/project/src/entry.ts": `
+				import "./foo.b"
+				import "./bar.js"
+				import "./baz.b.js"
+			`,
+
+			"/Users/user/project/src/foo.a.ts": `console.log('foo.a')`,
+			"/Users/user/project/src/foo.b.ts": `console.log('foo.b')`,
+			"/Users/user/project/src/foo.ts":   `console.log('foo')`,
+
+			"/Users/user/project/src/bar.ts": `console.log('bar')`,
+
+			"/Users/user/project/src/baz.a.ts": `console.log('baz.a')`,
+			"/Users/user/project/src/baz.b.ts": `console.log('baz.b')`,
+			"/Users/user/project/src/baz.ts":   `console.log('baz')`,
+
+			"/Users/user/project/tsconfig.json": `{
+				"compilerOptions": {
+					"moduleSuffixes": [".a", ".b", ""]
+				}
+			}`,
+		},
+		entryPaths: []string{"/Users/user/project/src/entry.ts"},
+		options: config.Options{
+			Mode:          config.ModeBundle,
+			AbsOutputFile: "/Users/user/project/out.js",
+		},
+	})
+}
+
+func TestTsConfigModuleSuffixesNoEmpty(t *testing.T) {
+	tsconfig_suite.expectBundled(t, bundled{
+		files: map[string]string{
+			"/Users/user/project/src/entry.ts": `
+				import "./foo.js"
+				import "./bar"
+			`,
+
+			"/Users/user/project/src/foo.b.ts": `console.log('foo.b')`,
+			"/Users/user/project/src/bar.ts":   `console.log('bar')`,
+
+			"/Users/user/project/tsconfig.json": `{
+				"compilerOptions": {
+					"moduleSuffixes": [".a", ".b"]
+				}
+			}`,
+		},
+		entryPaths: []string{"/Users/user/project/src/entry.ts"},
+		options: config.Options{
+			Mode:          config.ModeBundle,
+			AbsOutputFile: "/Users/user/project/out.js",
+		},
+		expectedScanLog: `Users/user/project/src/entry.ts: ERROR: Could not resolve "./bar"
+`,
+	})
+}

internal/bundler/snapshots/snapshots_tsconfig.txt

@@ -28,6 +28,30 @@ TestTsConfigJSX
 // Users/user/project/entry.tsx
 console.log(/* @__PURE__ */ R.c(R.F, null, /* @__PURE__ */ R.c("div", null), /* @__PURE__ */ R.c("div", null)));
 
+================================================================================
+TestTsConfigModuleSuffixesInsert
+---------- /Users/user/project/out.js ----------
+// Users/user/project/src/foo.a.ts
+console.log("foo.a");
+
+// Users/user/project/src/bar.a.ts
+console.log("bar.a");
+
+// Users/user/project/src/baz.a.ts
+console.log("baz.a");
+
+================================================================================
+TestTsConfigModuleSuffixesNoInsert
+---------- /Users/user/project/out.js ----------
+// Users/user/project/src/foo.b.ts
+console.log("foo.b");
+
+// Users/user/project/src/bar.ts
+console.log("bar");
+
+// Users/user/project/src/baz.b.ts
+console.log("baz.b");
+
 ================================================================================
 TestTsConfigNestedJSX
 ---------- /Users/user/project/out.js ----------