[embind] Simplify string.toWireType. NFC

- Simplify the type check - Remove the final argument from sringToUTF8 - Restructure the loop to avoid checking stdStringIsUTF8 twice
emscripten-core · Jan 10, 2025 · bf74d1c · bf74d1c
1 parent 5627123
commit bf74d1c
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Showing 3 changed files with 18 additions and 17 deletions.
diff --git a/src/embind/embind.js b/src/embind/embind.js
@@ -547,7 +547,8 @@ var LibraryEmbind = {
         var length;
         var valueIsOfTypeString = (typeof value == 'string');
 
-        if (!(valueIsOfTypeString || value instanceof Uint8Array || value instanceof Uint8ClampedArray || value instanceof Int8Array)) {
+        // We accept `string` or array views with single byte elements
+        if (!(valueIsOfTypeString || (ArrayBuffer.isView(value) && value.BYTES_PER_ELEMENT == 1))) {
           throwBindingError('Cannot pass non-string to std::string');
         }
         if (stdStringIsUTF8 && valueIsOfTypeString) {
@@ -560,10 +561,10 @@ var LibraryEmbind = {
         var base = _malloc({{{ POINTER_SIZE }}} + length + 1);
         var ptr = base + {{{ POINTER_SIZE }}};
         {{{ makeSetValue('base', '0', 'length', SIZE_TYPE) }}};
-        if (stdStringIsUTF8 && valueIsOfTypeString) {
-          stringToUTF8(value, ptr, length + 1);
-        } else {
-          if (valueIsOfTypeString) {
+        if (valueIsOfTypeString) {
+          if (stdStringIsUTF8) {
+            stringToUTF8(value, ptr, length);
+          } else {
             for (var i = 0; i < length; ++i) {
               var charCode = value.charCodeAt(i);
               if (charCode > 255) {
@@ -572,10 +573,10 @@ var LibraryEmbind = {
               }
               HEAPU8[ptr + i] = charCode;
             }
-          } else {
-            for (var i = 0; i < length; ++i) {
-              HEAPU8[ptr + i] = value[i];
-            }
+          }
+        } else {
+          for (var i = 0; i < length; ++i) {
+            HEAPU8[ptr + i] = value[i];
           }
         }
 

diff --git a/test/code_size/embind_hello_wasm.json b/test/code_size/embind_hello_wasm.json
@@ -1,10 +1,10 @@
 {
   "a.html": 552,
   "a.html.gz": 380,
-  "a.js": 9879,
-  "a.js.gz": 4288,
+  "a.js": 9371,
+  "a.js.gz": 4140,
   "a.wasm": 7348,
   "a.wasm.gz": 3375,
-  "total": 17779,
-  "total_gz": 8043
+  "total": 17271,
+  "total_gz": 7895
 }
diff --git a/test/code_size/embind_val_wasm.json b/test/code_size/embind_val_wasm.json
@@ -1,10 +1,10 @@
 {
   "a.html": 552,
   "a.html.gz": 380,
-  "a.js": 7153,
-  "a.js.gz": 3042,
+  "a.js": 6645,
+  "a.js.gz": 2892,
   "a.wasm": 9119,
   "a.wasm.gz": 4701,
-  "total": 16824,
-  "total_gz": 8123
+  "total": 16316,
+  "total_gz": 7973
 }