Avoid double-reporting the filename in JS library errors/warnings (#23787)

Author: sbc100

src/parseTools.mjs

@@ -152,7 +152,7 @@ export function preprocess(filename) {
             }
             const absPath = findIncludeFile(includeFile, path.dirname(filename));
             if (!absPath) {
-              error(`${filename}:${i + 1}: file not found: ${includeFile}`);
+              error(`file not found: ${includeFile}`, i + 1);
               continue;
             }
             const result = preprocess(absPath);
@@ -164,7 +164,7 @@ export function preprocess(filename) {
           }
         } else if (first === '#else') {
           if (showStack.length == 0) {
-            error(`${filename}:${i + 1}: #else without matching #if`);
+            error('#else without matching #if', i + 1);
           }
           const curr = showStack.pop();
           if (curr == IGNORE) {
@@ -174,23 +174,21 @@ export function preprocess(filename) {
           }
         } else if (first === '#endif') {
           if (showStack.length == 0) {
-            error(`${filename}:${i + 1}: #endif without matching #if`);
+            error('#endif without matching #if', i + 1);
           }
           showStack.pop();
         } else if (first === '#warning') {
           if (showCurrentLine()) {
-            warn(
-              `${filename}:${i + 1}: #warning ${trimmed.substring(trimmed.indexOf(' ')).trim()}`,
-            );
+            warn(`#warning ${trimmed.substring(trimmed.indexOf(' ')).trim()}`, i + 1);
           }
         } else if (first === '#error') {
           if (showCurrentLine()) {
-            error(`${filename}:${i + 1}: #error ${trimmed.substring(trimmed.indexOf(' ')).trim()}`);
+            error(`#error ${trimmed.substring(trimmed.indexOf(' ')).trim()}`, i + 1);
           }
         } else if (first === '#preprocess') {
           // Do nothing
         } else {
-          error(`${filename}:${i + 1}: Unknown preprocessor directive ${first}`);
+          error(`Unknown preprocessor directive ${first}`, i + 1);
         }
       } else {
         if (showCurrentLine()) {

src/utility.mjs

@@ -56,17 +56,19 @@ export function popCurrentFile() {
   currentFile.pop();
 }
 
-function errorPrefix() {
-  if (currentFile.length > 0) {
-    return currentFile[currentFile.length - 1] + ': ';
+function errorPrefix(lineNo) {
+  if (!currentFile.length) return '';
+  const filename = currentFile[currentFile.length - 1];
+  if (lineNo) {
+    return `${filename}:${lineNo}: `;
   } else {
-    return '';
+    return `${filename}: `;
   }
 }
 
-export function warn(msg) {
+export function warn(msg, lineNo) {
   warnings = true;
-  printErr(`warning: ${errorPrefix()}${msg}`);
+  printErr(`warning: ${errorPrefix(lineNo)}${msg}`);
 }
 
 const seenWarnings = new Set();
@@ -84,9 +86,9 @@ export function errorOccured() {
   return abortExecution;
 }
 
-export function error(msg) {
+export function error(msg, lineNo) {
   abortExecution = true;
-  printErr(`error: ${errorPrefix()}${msg}`);
+  printErr(`error: ${errorPrefix(lineNo)}${msg}`);
 }
 
 function range(size) {

test/test_other.py

@@ -4915,24 +4915,26 @@ def test_jslib_search_path(self):
 
   # Tests using the #warning directive in JS library files
   def test_jslib_warnings(self):
-    proc = self.run_process([EMCC, test_file('hello_world.c'), '--js-library', test_file('warning_in_js_libraries.js')], stdout=PIPE, stderr=PIPE)
+    shutil.copy(test_file('warning_in_js_libraries.js'), '.')
+    proc = self.run_process([EMCC, test_file('hello_world.c'), '--js-library', 'warning_in_js_libraries.js'], stdout=PIPE, stderr=PIPE)
     self.assertNotContained('This warning should not be present!', proc.stderr)
-    self.assertContained('warning_in_js_libraries.js:5: #warning This is a warning string!', proc.stderr)
-    self.assertContained('warning_in_js_libraries.js:7: #warning This is a second warning string!', proc.stderr)
+    self.assertContained('warning: warning_in_js_libraries.js:5: #warning This is a warning string!', proc.stderr)
+    self.assertContained('warning: warning_in_js_libraries.js:7: #warning This is a second warning string!', proc.stderr)
     self.assertContained('emcc: warning: warnings in JS library compilation [-Wjs-compiler]', proc.stderr)
 
-    err = self.expect_fail([EMCC, test_file('hello_world.c'), '--js-library', test_file('warning_in_js_libraries.js'), '-Werror'])
+    err = self.expect_fail([EMCC, test_file('hello_world.c'), '--js-library', 'warning_in_js_libraries.js', '-Werror'])
     self.assertNotContained('This warning should not be present!', err)
-    self.assertContained('warning_in_js_libraries.js:5: #warning This is a warning string!', err)
-    self.assertContained('warning_in_js_libraries.js:7: #warning This is a second warning string!', err)
+    self.assertContained('warning: warning_in_js_libraries.js:5: #warning This is a warning string!', err)
+    self.assertContained('warning: warning_in_js_libraries.js:7: #warning This is a second warning string!', err)
     self.assertContained('emcc: error: warnings in JS library compilation [-Wjs-compiler] [-Werror]', err)
 
   # Tests using the #error directive in JS library files
   def test_jslib_errors(self):
-    err = self.expect_fail([EMCC, test_file('hello_world.c'), '--js-library', test_file('error_in_js_libraries.js')])
+    shutil.copy(test_file('error_in_js_libraries.js'), '.')
+    err = self.expect_fail([EMCC, test_file('hello_world.c'), '--js-library', 'error_in_js_libraries.js'])
     self.assertNotContained('This error should not be present!', err)
-    self.assertContained('error_in_js_libraries.js:5: #error This is an error string!', err)
-    self.assertContained('error_in_js_libraries.js:7: #error This is a second error string!', err)
+    self.assertContained('error: error_in_js_libraries.js:5: #error This is an error string!', err)
+    self.assertContained('error: error_in_js_libraries.js:7: #error This is a second error string!', err)
 
   def test_jslib_include(self):
     create_file('inc.js', '''