Avoid resetting process.exitCode when initializing HermesParserWASM (#…

…989) Summary: Pull Request resolved: #989 The default emscripten code overrides the `process.exitCode` value to `0` on module init. This means if someone has already set an `exitCode` it will be reset. This change fixes this by switching emscripten to use the `MODULARIZE` flag which allows us to pass in function overrides, we then pass a modified implementation of `quit` that only adds the exitCode if its non zero. Fixes: #978 Reviewed By: tmikov Differential Revision: D45705102 fbshipit-source-id: 915ef98348be0b6f6536ea902a8b62a10490a66b
facebook · May 11, 2023 · d1be3ff · d1be3ff
1 parent ae61ae2
commit d1be3ff
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Showing 4 changed files with 94 additions and 55 deletions.
diff --git a/tools/hermes-parser/CMakeLists.txt b/tools/hermes-parser/CMakeLists.txt
@@ -21,6 +21,7 @@ if (EMSCRIPTEN)
   target_link_options(hermes-parser-wasm PRIVATE "SHELL: -s ALLOW_MEMORY_GROWTH=1")
   target_link_options(hermes-parser-wasm PRIVATE
     "SHELL: -s EXTRA_EXPORTED_RUNTIME_METHODS=[cwrap,ccall]")
+  target_link_options(hermes-parser-wasm PRIVATE "SHELL: -s MODULARIZE=1")
   target_link_options(hermes-parser-wasm PRIVATE "SHELL: -s EXPORT_NAME=hermes_parser_wasm")
   target_link_options(hermes-parser-wasm PRIVATE
     "SHELL: -s BINARYEN_ASYNC_COMPILATION=0 -s SINGLE_FILE=1 -s WASM_ASYNC_COMPILATION=0")

diff --git a/tools/hermes-parser/js/hermes-parser/src/HermesParser.js b/tools/hermes-parser/js/hermes-parser/src/HermesParser.js
@@ -14,58 +14,90 @@ import type {HermesNode} from './HermesAST';
 import type {ParserOptions} from './ParserOptions';
 
 import HermesParserDeserializer from './HermesParserDeserializer';
-import HermesParserWASM from './HermesParserWASM';
-
-const hermesParse = HermesParserWASM.cwrap('hermesParse', 'number', [
-  'number',
-  'number',
-  'number',
-  'number',
-  'number',
-  'number',
-]);
-
-const hermesParseResult_free = HermesParserWASM.cwrap(
-  'hermesParseResult_free',
-  'void',
-  ['number'],
-);
-
-const hermesParseResult_getError = HermesParserWASM.cwrap(
-  'hermesParseResult_getError',
-  'string',
-  ['number'],
-);
-
-const hermesParseResult_getErrorLine = HermesParserWASM.cwrap(
-  'hermesParseResult_getErrorLine',
-  'number',
-  ['number'],
-);
-
-const hermesParseResult_getErrorColumn = HermesParserWASM.cwrap(
-  'hermesParseResult_getErrorColumn',
-  'number',
-  ['number'],
-);
-
-const hermesParseResult_getProgramBuffer = HermesParserWASM.cwrap(
-  'hermesParseResult_getProgramBuffer',
-  'number',
-  ['number'],
-);
-
-const hermesParseResult_getPositionBuffer = HermesParserWASM.cwrap(
-  'hermesParseResult_getPositionBuffer',
-  'number',
-  ['number'],
-);
-
-const hermesParseResult_getPositionBufferSize = HermesParserWASM.cwrap(
-  'hermesParseResult_getPositionBufferSize',
-  'number',
-  ['number'],
-);
+import HermesParserWASMModule from './HermesParserWASM';
+
+let HermesParserWASM;
+let hermesParse;
+let hermesParseResult_free;
+let hermesParseResult_getError;
+let hermesParseResult_getErrorLine;
+let hermesParseResult_getErrorColumn;
+let hermesParseResult_getProgramBuffer;
+let hermesParseResult_getPositionBuffer;
+let hermesParseResult_getPositionBufferSize;
+
+/**
+ * Init the WASM wrapper code generated by `emscripten` to preparse the
+ * HermesParser WASM code.
+ */
+function initHermesParserWASM() {
+  if (HermesParserWASM != null) {
+    return;
+  }
+
+  HermesParserWASM = HermesParserWASMModule({
+    /**
+     * The emscripten version of `quit` unconditionally assigns the `status` to
+     * `process.exitCode` which overrides any pre-existing code that has been
+     * set, even if it is non zero. For our use case we never want an
+     * `exitCode` to be set so this override removes that functionality.
+     */
+    quit(_status: number, toThrow: Error) {
+      throw toThrow;
+    },
+  });
+
+  hermesParse = HermesParserWASM.cwrap('hermesParse', 'number', [
+    'number',
+    'number',
+    'number',
+    'number',
+    'number',
+    'number',
+  ]);
+
+  hermesParseResult_free = HermesParserWASM.cwrap(
+    'hermesParseResult_free',
+    'void',
+    ['number'],
+  );
+
+  hermesParseResult_getError = HermesParserWASM.cwrap(
+    'hermesParseResult_getError',
+    'string',
+    ['number'],
+  );
+
+  hermesParseResult_getErrorLine = HermesParserWASM.cwrap(
+    'hermesParseResult_getErrorLine',
+    'number',
+    ['number'],
+  );
+
+  hermesParseResult_getErrorColumn = HermesParserWASM.cwrap(
+    'hermesParseResult_getErrorColumn',
+    'number',
+    ['number'],
+  );
+
+  hermesParseResult_getProgramBuffer = HermesParserWASM.cwrap(
+    'hermesParseResult_getProgramBuffer',
+    'number',
+    ['number'],
+  );
+
+  hermesParseResult_getPositionBuffer = HermesParserWASM.cwrap(
+    'hermesParseResult_getPositionBuffer',
+    'number',
+    ['number'],
+  );
+
+  hermesParseResult_getPositionBufferSize = HermesParserWASM.cwrap(
+    'hermesParseResult_getPositionBufferSize',
+    'number',
+    ['number'],
+  );
+}
 
 // Copy a string into the WASM heap and null-terminate
 function copyToHeap(buffer: Buffer, addr: number) {
@@ -74,6 +106,8 @@ function copyToHeap(buffer: Buffer, addr: number) {
 }
 
 export function parse(source: string, options: ParserOptions): HermesNode {
+  initHermesParserWASM();
+
   // Allocate space on heap for source text
   const sourceBuffer = Buffer.from(source, 'utf8');
   const sourceAddr = HermesParserWASM._malloc(sourceBuffer.length + 1);

diff --git a/tools/hermes-parser/js/hermes-parser/src/HermesParserDeserializer.js b/tools/hermes-parser/js/hermes-parser/src/HermesParserDeserializer.js
@@ -16,7 +16,7 @@ import type {
   HermesToken,
   HermesComment,
 } from './HermesAST';
-import typeof HermesParserWASM from './HermesParserWASM';
+import type {HermesParserWASM} from './HermesParserWASM';
 import type {ParserOptions} from './ParserOptions';
 
 import HermesParserDecodeUTF8String from './HermesParserDecodeUTF8String';

diff --git a/tools/hermes-parser/js/hermes-parser/src/HermesParserWASM.js.flow b/tools/hermes-parser/js/hermes-parser/src/HermesParserWASM.js.flow
@@ -12,7 +12,11 @@ type INTENTIONAL_ANY = $FlowFixMe;
 type JSType = 'number' | 'string' | 'array' | 'boolean';
 type CBoolean = ?(number | boolean);
 
-type HermesParserWASM = $ReadOnly<{
+type WASMModuleOverrides = $ReadOnly<{
+  quit(status: number, toThrow: Error): void,
+}>;
+
+export type HermesParserWASM = $ReadOnly<{
   HEAP8: Int8Array,
   HEAP16: Int16Array,
   HEAP32: Int32Array,
@@ -72,4 +76,4 @@ type HermesParserWASM = $ReadOnly<{
   stackRestore(ptr: number): void,
 }>;
 
-declare module.exports: HermesParserWASM;
+declare module.exports: WASMModuleOverrides => HermesParserWASM;