copy a typescript compiler tsconfig extends bug

evanw · Dec 4, 2022 · b9e9513 · b9e9513
1 parent 8821fbe
commit b9e9513
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Showing 3 changed files with 141 additions and 3 deletions.
diff --git a/internal/bundler/bundler_tsconfig_test.go b/internal/bundler/bundler_tsconfig_test.go
@@ -2037,3 +2037,111 @@ func TestTsConfigAlwaysStrictTrueEmitDirectiveBundleESM(t *testing.T) {
 		},
 	})
 }
+
+func TestTsConfigExtendsDotWithoutSlash(t *testing.T) {
+	tsconfig_suite.expectBundled(t, bundled{
+		files: map[string]string{
+			"/Users/user/project/src/main.ts": `
+				console.log(123n)
+			`,
+			"/Users/user/project/src/foo.json": `{
+				"extends": "."
+			}`,
+			"/Users/user/project/src/tsconfig.json": `{
+				"compilerOptions": {
+					"target": "ES6"
+				}
+			}`,
+		},
+		entryPaths: []string{"/Users/user/project/src/main.ts"},
+		options: config.Options{
+			Mode:             config.ModeBundle,
+			AbsOutputDir:     "/Users/user/project/out",
+			OutputFormat:     config.FormatESModule,
+			TsConfigOverride: "/Users/user/project/src/foo.json",
+		},
+		expectedScanLog: `Users/user/project/src/main.ts: ERROR: Big integer literals are not available in the configured target environment ("ES6")
+Users/user/project/src/tsconfig.json: NOTE: The target environment was set to "ES6" here:
+`,
+	})
+}
+
+func TestTsConfigExtendsDotDotWithoutSlash(t *testing.T) {
+	tsconfig_suite.expectBundled(t, bundled{
+		files: map[string]string{
+			"/Users/user/project/src/main.ts": `
+				console.log(123n)
+			`,
+			"/Users/user/project/src/tsconfig.json": `{
+				"extends": ".."
+			}`,
+			"/Users/user/project/tsconfig.json": `{
+				"compilerOptions": {
+					"target": "ES6"
+				}
+			}`,
+		},
+		entryPaths: []string{"/Users/user/project/src/main.ts"},
+		options: config.Options{
+			Mode:         config.ModeBundle,
+			AbsOutputDir: "/Users/user/project/out",
+			OutputFormat: config.FormatESModule,
+		},
+		expectedScanLog: `Users/user/project/src/main.ts: ERROR: Big integer literals are not available in the configured target environment ("ES6")
+Users/user/project/tsconfig.json: NOTE: The target environment was set to "ES6" here:
+`,
+	})
+}
+
+func TestTsConfigExtendsDotWithSlash(t *testing.T) {
+	tsconfig_suite.expectBundled(t, bundled{
+		files: map[string]string{
+			"/Users/user/project/src/main.ts": `
+				console.log(123n)
+			`,
+			"/Users/user/project/src/foo.json": `{
+				"extends": "./"
+			}`,
+			"/Users/user/project/src/tsconfig.json": `{
+				"compilerOptions": {
+					"target": "ES6"
+				}
+			}`,
+		},
+		entryPaths: []string{"/Users/user/project/src/main.ts"},
+		options: config.Options{
+			Mode:             config.ModeBundle,
+			AbsOutputDir:     "/Users/user/project/out",
+			OutputFormat:     config.FormatESModule,
+			TsConfigOverride: "/Users/user/project/src/foo.json",
+		},
+		expectedScanLog: `Users/user/project/src/foo.json: WARNING: Cannot find base config file "./"
+`,
+	})
+}
+
+func TestTsConfigExtendsDotDotWithSlash(t *testing.T) {
+	tsconfig_suite.expectBundled(t, bundled{
+		files: map[string]string{
+			"/Users/user/project/src/main.ts": `
+				console.log(123n)
+			`,
+			"/Users/user/project/src/tsconfig.json": `{
+				"extends": "../"
+			}`,
+			"/Users/user/project/tsconfig.json": `{
+				"compilerOptions": {
+					"target": "ES6"
+				}
+			}`,
+		},
+		entryPaths: []string{"/Users/user/project/src/main.ts"},
+		options: config.Options{
+			Mode:         config.ModeBundle,
+			AbsOutputDir: "/Users/user/project/out",
+			OutputFormat: config.FormatESModule,
+		},
+		expectedScanLog: `Users/user/project/src/tsconfig.json: WARNING: Cannot find base config file "../"
+`,
+	})
+}
diff --git a/internal/bundler/snapshots/snapshots_tsconfig.txt b/internal/bundler/snapshots/snapshots_tsconfig.txt
@@ -82,6 +82,18 @@ var foo = 123;
 // Users/user/project/src/entry.ts
 console.log(foo);
 
+================================================================================
+TestTsConfigExtendsDotDotWithSlash
+---------- /Users/user/project/out/main.js ----------
+// Users/user/project/src/main.ts
+console.log(123n);
+
+================================================================================
+TestTsConfigExtendsDotWithSlash
+---------- /Users/user/project/out/main.js ----------
+// Users/user/project/src/main.ts
+console.log(123n);
+
 ================================================================================
 TestTsConfigJSX
 ---------- /Users/user/project/out.js ----------

diff --git a/internal/resolver/resolver.go b/internal/resolver/resolver.go
@@ -1095,10 +1095,28 @@ func (r resolverQuery) parseTSConfig(file string, visited map[string]bool) (*TSC
 				current = next
 			}
 		} else {
-			// If this is a regular path, search relative to the enclosing directory
 			extendsFile := extends
-			if !r.fs.IsAbs(extends) {
-				extendsFile = r.fs.Join(fileDir, extends)
+
+			// The TypeScript compiler has a strange behavior that seems like a bug
+			// where "." and ".." behave differently than other forms such as "./."
+			// or "../." and are interpreted as having an implicit "tsconfig.json"
+			// suffix.
+			//
+			// I believe their bug is caused by some parts of their code checking for
+			// relative paths using the literal "./" and "../" prefixes (requiring
+			// the slash) and other parts checking using the regular expression
+			// /^\.\.?($|[\\/])/ (with the slash optional).
+			//
+			// In any case, people are now relying on this behavior. One example is
+			// this: https://github.com/esbuild-kit/tsx/pull/158. So we replicate this
+			// bug in esbuild as well.
+			if extendsFile == "." || extendsFile == ".." {
+				extendsFile += "/tsconfig.json"
+			}
+
+			// If this is a regular path, search relative to the enclosing directory
+			if !r.fs.IsAbs(extendsFile) {
+				extendsFile = r.fs.Join(fileDir, extendsFile)
 			}
 			base, err := r.parseTSConfig(extendsFile, visited)