fix: handle regexp as default export (#167)

guybedford · Mar 19, 2024 · d78f7d4 · d78f7d4
1 parent c357368
commit d78f7d4
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Showing 6 changed files with 30 additions and 2 deletions.
diff --git a/lexer.js b/lexer.js
@@ -186,6 +186,7 @@ export function parse (_source, _name) {
           // - if a closing brace or paren, what token came before the corresponding
           //   opening brace or paren (lastOpenTokenIndex)
           const lastToken = source.charCodeAt(lastTokenPos);
+          const lastExport = exports[exports.length - 1];
           if (isExpressionPunctuator(lastToken) &&
               !(lastToken === 46/*.*/ && (source.charCodeAt(lastTokenPos - 1) >= 48/*0*/ && source.charCodeAt(lastTokenPos - 1) <= 57/*9*/)) &&
               !(lastToken === 43/*+*/ && source.charCodeAt(lastTokenPos - 1) === 43/*+*/) && !(lastToken === 45/*-*/ && source.charCodeAt(lastTokenPos - 1) === 45/*-*/) ||
@@ -197,6 +198,11 @@ export function parse (_source, _name) {
             regularExpression();
             lastSlashWasDivision = false;
           }
+          else if (lastExport && lastTokenPos >= lastExport.s && lastTokenPos <= lastExport.e) {
+            // export default /some-regexp/
+            regularExpression();
+            lastSlashWasDivision = false;
+          }
           else {
             lastSlashWasDivision = true;
           }

diff --git a/lib/lexer.asm.js b/lib/lexer.asm.js
diff --git a/lib/lexer.emcc.asm.js b/lib/lexer.emcc.asm.js
diff --git a/lib/lexer.wasm b/lib/lexer.wasm
diff --git a/src/lexer.c b/src/lexer.c
@@ -195,6 +195,11 @@ bool parse () {
             regularExpression();
             lastSlashWasDivision = false;
           }
+          else if (export_write_head != NULL && lastTokenPos >= export_write_head->start && lastTokenPos <= export_write_head->end) {
+            // export default /some-regexp/
+            regularExpression();
+            lastSlashWasDivision = false;
+          }
           else {
             // Final check - if the last token was "break x" or "continue x"
             while (lastTokenPos > source && !isBrOrWsOrPunctuatorNotDot(*(--lastTokenPos)));

diff --git a/test/_unit.cjs b/test/_unit.cjs
@@ -252,6 +252,23 @@ suite('Lexer', () => {
     `);
   });
 
+  test('Regexp default export', () => {
+    const source = `
+      export default /[\`]/
+      export default 1/2
+      export default /* asdf */ 1/2
+      export default /* asdf */ /regex/
+      export default
+      // line comment
+      /regex/
+      export default
+      // line comment
+      1 / 2
+    `;
+    const [, exports] = parse(source);
+    assert.deepStrictEqual(exports.map(expt => expt.n), ['default', 'default', 'default', 'default', 'default', 'default']);
+  });
+
   if (!js)
   test('Regexp keyword prefixes', () => {
     const [imports] = parse(`