ts "import id =" syntax is not esm syntax

evanw · Feb 8, 2021 · cd08847 · cd08847
1 parent 6da51d4
commit cd08847
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Showing 3 changed files with 18 additions and 10 deletions.
diff --git a/internal/bundler/snapshots/snapshots_default.txt b/internal/bundler/snapshots/snapshots_default.txt
@@ -2179,6 +2179,12 @@ var require_dummy = __commonJS((exports) => {
   var dummy = 123;
 });
 
+// es6-import-assign.ts
+var require_es6_import_assign = __commonJS((exports) => {
+  var x2 = require_dummy();
+  console.log(exports);
+});
+
 // es6-import-dynamic.js
 var require_es6_import_dynamic = __commonJS((exports) => {
   Promise.resolve().then(() => __toModule(require_dummy()));
@@ -2295,11 +2301,8 @@ var import_cjs = __toModule(require_cjs());
 var import_dummy = __toModule(require_dummy());
 console.log(void 0);
 
-// es6-import-assign.ts
-var x = require_dummy();
-console.log(void 0);
-
 // entry.js
+var import_es6_import_assign = __toModule(require_es6_import_assign());
 var import_es6_import_dynamic = __toModule(require_es6_import_dynamic());
 
 // es6-import-meta.js
@@ -2365,7 +2368,7 @@ console.log(void 0);
 var import_es6_export_assign = __toModule(require_es6_export_assign());
 
 // es6-export-import-assign.ts
-var x2 = require_dummy();
+var x = require_dummy();
 console.log(void 0);
 
 // entry.js

diff --git a/internal/js_parser/js_parser.go b/internal/js_parser/js_parser.go
@@ -4909,7 +4909,7 @@ func (p *parser) parseStmt(opts parseStmtOpts) js_ast.Stmt {
 		return js_ast.Stmt{Loc: loc, Data: &js_ast.SEmpty{}}
 
 	case js_lexer.TExport:
-		oldExportKeyword := p.es6ExportKeyword
+		previousExportKeyword := p.es6ExportKeyword
 		if opts.isModuleScope {
 			p.es6ExportKeyword = p.lexer.Range()
 		} else if !opts.isNamespaceScope {
@@ -5190,7 +5190,7 @@ func (p *parser) parseStmt(opts parseStmtOpts) js_ast.Stmt {
 
 		case js_lexer.TEquals:
 			// "export = value;"
-			p.es6ExportKeyword = oldExportKeyword // Never mind it's CommonJS syntax instead of ECMAScript module syntax
+			p.es6ExportKeyword = previousExportKeyword // This wasn't an ESM export statement after all
 			if p.options.ts.Parse {
 				p.lexer.Next()
 				value := p.parseExpr(js_ast.LLowest)
@@ -5600,7 +5600,7 @@ func (p *parser) parseStmt(opts parseStmtOpts) js_ast.Stmt {
 		case js_lexer.TOpenParen, js_lexer.TDot:
 			// "import('path')"
 			// "import.meta"
-			p.es6ImportKeyword = previousImportKeyword // This wasn't an import statement after all
+			p.es6ImportKeyword = previousImportKeyword // This wasn't an ESM import statement after all
 			expr := p.parseSuffix(p.parseImportExpr(loc, js_ast.LLowest), js_ast.LLowest, nil, 0)
 			p.lexer.ExpectOrInsertSemicolon()
 			return js_ast.Stmt{Loc: loc, Data: &js_ast.SExpr{Value: expr}}
@@ -5689,6 +5689,7 @@ func (p *parser) parseStmt(opts parseStmtOpts) js_ast.Stmt {
 
 				// Parse TypeScript import assignment statements
 				if p.lexer.Token == js_lexer.TEquals || opts.isExport || (opts.isNamespaceScope && !opts.isTypeScriptDeclare) {
+					p.es6ImportKeyword = previousImportKeyword // This wasn't an ESM import statement after all
 					return p.parseTypeScriptImportEqualsStmt(loc, opts, stmt.DefaultName.Loc, defaultName)
 				}
 			}

diff --git a/internal/js_parser/ts_parser_test.go b/internal/js_parser/ts_parser_test.go
@@ -1312,15 +1312,19 @@ func TestTSImport(t *testing.T) {
 
 // This is TypeScript-specific export syntax
 func TestTSExportEquals(t *testing.T) {
-	expectPrintedTS(t, "export = []", "module.exports = [];\n")
-
 	// This use of the "export" keyword should not trigger strict mode because
 	// this syntax works in CommonJS modules, not in ECMAScript modules
+	expectPrintedTS(t, "export = []", "module.exports = [];\n")
 	expectPrintedTS(t, "export = []; with ({}) ;", "with ({})\n  ;\nmodule.exports = [];\n")
 }
 
 // This is TypeScript-specific import syntax
 func TestTSImportEquals(t *testing.T) {
+	// This use of the "export" keyword should not trigger strict mode because
+	// this syntax works in CommonJS modules, not in ECMAScript modules
+	expectPrintedTS(t, "import x = require('y')", "const x = require(\"y\");\n")
+	expectPrintedTS(t, "import x = require('y'); with ({}) ;", "const x = require(\"y\");\nwith ({})\n  ;\n")
+
 	expectPrintedTS(t, "import x = require('foo'); x()", "const x = require(\"foo\");\nx();\n")
 	expectPrintedTS(t, "import x = require('foo')\nx()", "const x = require(\"foo\");\nx();\n")
 	expectPrintedTS(t, "import x = require\nx()", "const x = require;\nx();\n")