Remove used of String.substr from library code. NFC (#23513)

String.substr is deprecated.

Author: sbc100

src/cpuprofiler.js

@@ -225,7 +225,7 @@ var emscriptenCpuProfiler = {
           if (i != 2) cs += ' <- ';
           var fn = funcs[i];
           var at = fn.indexOf('@');
-          if (at != -1) fn = fn.substr(0, at);
+          if (at != -1) fn = fn.slice(0, at);
           fn = fn.trim();
           cs += '"' + fn + '"';
         }

src/emrun_prejs.js

@@ -9,7 +9,7 @@
 
 // Route URL GET parameters to argc+argv
 if (typeof window == 'object') {
-  Module['arguments'] = window.location.search.substr(1).trim().split('&');
+  Module['arguments'] = window.location.search.slice(1).trim().split('&');
   for (let i = 0; i < Module['arguments'].length; ++i) {
     Module['arguments'][i] = decodeURI(Module['arguments'][i]);
   }

src/lib/libbootstrap.js

@@ -43,7 +43,7 @@ addToLibrary({
     // extra effort to support printf, even without a filesystem. very partial, very hackish
     var result = formatString(format, varargs);
     var string = intArrayToString(result);
-    if (string[string.length-1] === '\n') string = string.substr(0, string.length-1); // remove a final \n, as Module.print will do that
+    if (string.endsWith('\n')) string = string.slice(0, -1); // remove a final \n, as Module.print will do that
     out(string);
     return result.length;
   },
@@ -52,8 +52,8 @@ addToLibrary({
   puts: (s) => {
     // extra effort to support puts, even without a filesystem. very partial, very hackish
     var result = UTF8ToString(s);
-    var string = result.substr(0);
-    if (string[string.length-1] === '\n') string = string.substr(0, string.length-1); // remove a final \n, as Module.print will do that
+    var string = result;
+    if (string.endsWith('\n')) string = string.slice(0, -1); // remove a final \n, as Module.print will do that
     out(string);
     return result.length;
   },

src/lib/libbrowser.js

@@ -88,7 +88,7 @@ var LibraryBrowser = {
 
       var audioPlugin = {};
       audioPlugin['canHandle'] = function audioPlugin_canHandle(name) {
-        return !Module['noAudioDecoding'] && name.substr(-4) in { '.ogg': 1, '.wav': 1, '.mp3': 1 };
+        return !Module['noAudioDecoding'] && name.slice(-4) in { '.ogg': 1, '.wav': 1, '.mp3': 1 };
       };
       audioPlugin['handle'] = function audioPlugin_handle(byteArray, name, onload, onerror) {
         var done = false;
@@ -138,7 +138,7 @@ var LibraryBrowser = {
             }
             return ret;
           }
-          audio.src = 'data:audio/x-' + name.substr(-3) + ';base64,' + encode64(byteArray);
+          audio.src = 'data:audio/x-' + name.slice(-3) + ';base64,' + encode64(byteArray);
           finish(audio); // we don't wait for confirmation this worked - but it's worth trying
         };
         audio.src = url;
@@ -348,7 +348,7 @@ var LibraryBrowser = {
         'ogg': 'audio/ogg',
         'wav': 'audio/wav',
         'mp3': 'audio/mpeg'
-      }[name.substr(name.lastIndexOf('.')+1)];
+      }[name.slice(name.lastIndexOf('.')+1)];
     },
 
     getUserMedia(func) {
@@ -732,7 +732,7 @@ var LibraryBrowser = {
     var styleSheet = document.styleSheets[0];
     var rules = styleSheet.cssRules;
     for (var i = 0; i < rules.length; i++) {
-      if (rules[i].cssText.substr(0, 6) == 'canvas') {
+      if (rules[i].cssText.startsWith('canvas')) {
         styleSheet.deleteRule(i);
         i--;
       }

src/lib/libc_preprocessor.js

@@ -96,7 +96,7 @@ addToLibrary({
           }
         } else if (kind == 1/*operator symbol*/) {
           // Lookahead for two-character operators.
-          var op2 = exprString.substr(i, 2);
+          var op2 = exprString.slice(i, i + 2);
           if (['<=', '>=', '==', '!=', '&&', '||'].includes(op2)) {
             out.push(op2);
             ++i;

src/lib/libembind_shared.js

@@ -128,9 +128,9 @@ var LibraryEmbindShared = {
     const argsIndex = signature.indexOf("(");
     if (argsIndex !== -1) {
 #if ASSERTIONS
-      assert(signature[signature.length - 1] == ")", "Parentheses for argument names should match.");
+      assert(signature.endsWith(")"), "Parentheses for argument names should match.");
 #endif
-      return signature.substr(0, argsIndex);
+      return signature.slice(0, argsIndex);
     } else {
       return signature;
     }
@@ -141,9 +141,9 @@ var LibraryEmbindShared = {
     const argsIndex = signature.indexOf("(") + 1;
     if (argsIndex !== 0) {
 #if ASSERTIONS
-      assert(signature[signature.length - 1] == ")", "Parentheses for argument names should match.");
+      assert(signature.endsWith(")"), "Parentheses for argument names should match.");
 #endif
-      return signature.substr(argsIndex, signature.length - argsIndex - 1).replaceAll(" ", "").split(",").filter(n => n.length);
+      return signature.slice(argsIndex, -1).replaceAll(" ", "").split(",").filter(n => n.length);
     } else {
       return [];
     }

src/lib/libexports.js

@@ -10,7 +10,7 @@ addToLibrary({
     name = UTF8ToString(name);
     // Wasm backend does not use C name mangling on exports,
     // so adjust for that manually.
-    if (name[0] == '_') name = name.substr(1);
+    if (name[0] == '_') name = name.slice(1);
     var exportedFunc = wasmExports[name];
     if (exportedFunc) {
       // Record the created function pointer to each function object,

src/lib/libformatString.js

@@ -290,7 +290,7 @@ addToLibrary({
             // Move sign to prefix so we zero-pad after the sign
             if (argText.charAt(0) == '-') {
               prefix = '-' + prefix;
-              argText = argText.substr(1);
+              argText = argText.slice(1);
             }
 
             // Add padding.
@@ -417,7 +417,7 @@ addToLibrary({
                 ret.push({{{ makeGetValue('arg++', 0, 'u8') }}});
               }
             } else {
-              ret = ret.concat(intArrayFromString('(null)'.substr(0, argLength), true));
+              ret = ret.concat(intArrayFromString('(null)'.slice(0, argLength), true));
             }
             if (flagLeftAlign) {
               while (argLength < width--) {

src/lib/libfs.js

@@ -43,7 +43,7 @@ FS.ignorePermissions = false;
 FS.createPreloadedFile = FS_createPreloadedFile;
 FS.staticInit();
 // Set module methods based on EXPORTED_RUNTIME_METHODS
-{{{ EXPORTED_RUNTIME_METHODS.filter((func) => func.startsWith('FS_')).map((func) => 'Module["' + func + '"] = FS.' + func.substr(3) + ";\n").reduce((str, func) => str + func, '') }}}`;
+{{{ EXPORTED_RUNTIME_METHODS.filter((func) => func.startsWith('FS_')).map((func) => 'Module["' + func + '"] = FS.' + func.slice(3) + ";\n").reduce((str, func) => str + func, '') }}}`;
   },
   $FS: {
     root: null,

src/lib/libhtml5.js

@@ -360,7 +360,7 @@ var LibraryHTML5 = {
     // represents the set of OffscreenCanvases owned by the current calling thread.
 
     // First check out the list of OffscreenCanvases by CSS selector ID ('#myCanvasID')
-    return GL.offscreenCanvases[target.substr(1)] // Remove '#' prefix
+    return GL.offscreenCanvases[target.slice(1)] // Remove '#' prefix
     // If not found, if one is querying by using DOM tag name selector 'canvas', grab the first
     // OffscreenCanvas that we can find.
      || (target == 'canvas' && Object.keys(GL.offscreenCanvases)[0])