Bug 674283 - Add source map urls to JSScript. r=jorendorff.

js/src/jsapi-tests/testScriptInfo.cpp

@@ -16,7 +16,18 @@ try {              \n\
 catch (e)          \n\
 {                  \n\
 	 xx += 1;  \n\
-}";
+}\n\
+//@sourceMappingURL=http://example.com/path/to/source-map.json";
+
+
+static bool
+CharsMatch(const jschar *p, const char *q) {
+    while (*q) {
+        if (*p++ != *q++)
+            return false;
+    }
+    return true;
+}
 
 // Bug 670958 - fix JS_GetScriptLineExtent, among others
 BEGIN_TEST(testScriptInfo)
@@ -34,7 +45,8 @@ BEGIN_TEST(testScriptInfo)
     CHECK_EQUAL(JS_PCToLineNumber(cx, script, start), startLine);
     CHECK_EQUAL(JS_GetScriptLineExtent(cx, script), 10);
     CHECK(strcmp(JS_GetScriptFilename(cx, script), __FILE__) == 0);
-    
+    CHECK(CharsMatch(JS_GetScriptSourceMap(cx, script), "http://example.com/path/to/source-map.json"));
+
     return true;
 }
 END_TEST(testScriptInfo)

js/src/jsdbgapi.cpp

@@ -23,6 +23,7 @@
  * the Initial Developer. All Rights Reserved.
  *
  * Contributor(s):
+ *   Nick Fitzgerald <nfitzgerald@mozilla.com>
  *
  * Alternatively, the contents of this file may be used under the terms of
  * either of the GNU General Public License Version 2 or later (the "GPL"),
@@ -422,7 +423,7 @@ JS_ClearTrap(JSContext *cx, JSScript *script, jsbytecode *pc,
              JSTrapHandler *handlerp, jsval *closurep)
 {
     JSTrap *trap;
-    
+
     DBG_LOCK(cx->runtime);
     trap = FindTrap(cx->runtime, script, pc);
     if (handlerp)
@@ -1045,6 +1046,12 @@ JS_GetScriptFilename(JSContext *cx, JSScript *script)
     return script->filename;
 }
 
+JS_PUBLIC_API(const jschar *)
+JS_GetScriptSourceMap(JSContext *cx, JSScript *script)
+{
+    return script->sourceMap;
+}
+
 JS_PUBLIC_API(uintN)
 JS_GetScriptBaseLineNumber(JSContext *cx, JSScript *script)
 {
@@ -1131,7 +1138,7 @@ JS_EvaluateInStackFrame(JSContext *cx, JSStackFrame *fp,
     jschar *chars;
     JSBool ok;
     size_t len = length;
-    
+
     if (!CheckDebugMode(cx))
         return JS_FALSE;
 

js/src/jsdbgapi.h

@@ -23,6 +23,7 @@
  * the Initial Developer. All Rights Reserved.
  *
  * Contributor(s):
+ *   Nick Fitzgerald <nfitzgerald@mozilla.com>
  *
  * Alternatively, the contents of this file may be used under the terms of
  * either of the GNU General Public License Version 2 or later (the "GPL"),
@@ -349,6 +350,9 @@ JS_GetValidFrameCalleeObject(JSContext *cx, JSStackFrame *fp, jsval *vp);
 extern JS_PUBLIC_API(const char *)
 JS_GetScriptFilename(JSContext *cx, JSScript *script);
 
+extern JS_PUBLIC_API(const jschar *)
+JS_GetScriptSourceMap(JSContext *cx, JSScript *script);
+
 extern JS_PUBLIC_API(uintN)
 JS_GetScriptBaseLineNumber(JSContext *cx, JSScript *script);
 

js/src/jsscan.cpp

@@ -23,6 +23,7 @@
  * the Initial Developer. All Rights Reserved.
  *
  * Contributor(s):
+ *   Nick Fitzgerald <nfitzgerald@mozilla.com>
  *
  * Alternatively, the contents of this file may be used under the terms of
  * either of the GNU General Public License Version 2 or later (the "GPL"),
@@ -179,6 +180,7 @@ TokenStream::init(const jschar *base, size_t length, const char *fn, uintN ln, J
     userbuf.init(base, length);
     linebase = base;
     prevLinebase = NULL;
+    sourceMap = NULL;
 
     JSSourceHandler listener = cx->debugHooks->sourceHandler;
     void *listenerData = cx->debugHooks->sourceHandlerData;
@@ -247,6 +249,8 @@ TokenStream::~TokenStream()
 {
     if (flags & TSF_OWNFILENAME)
         cx->free_((void *) filename);
+    if (sourceMap)
+        cx->free_(sourceMap);
 }
 
 /* Use the fastest available getc. */
@@ -1132,6 +1136,19 @@ TokenStream::matchUnicodeEscapeIdent(int32 *cp)
     return false;
 }
 
+/*
+ * Helper function which returns true if the first length(q) characters in p are
+ * the same as the characters in q.
+ */
+static bool
+CharsMatch(const jschar *p, const char *q) {
+    while (*q) {
+        if (*p++ != *q++)
+            return false;
+    }
+    return true;
+}
+
 bool
 TokenStream::getAtLine()
 {
@@ -1145,12 +1162,7 @@ TokenStream::getAtLine()
      * "//@line 123\n" sets the number of the *next* line after the
      * comment to 123.  If we reach here, we've already seen "//".
      */
-    if (peekChars(5, cp) &&
-        cp[0] == '@' &&
-        cp[1] == 'l' &&
-        cp[2] == 'i' &&
-        cp[3] == 'n' &&
-        cp[4] == 'e') {
+    if (peekChars(5, cp) && CharsMatch(cp, "@line")) {
         skipChars(5);
         while ((c = getChar()) != '\n' && c != EOF && IsSpaceOrBOM2(c))
             continue;
@@ -1200,6 +1212,42 @@ TokenStream::getAtLine()
     return true;
 }
 
+bool
+TokenStream::getAtSourceMappingURL()
+{
+    jschar peeked[18];
+
+    /* Match comments of the form @sourceMappingURL=<url> */
+    if (peekChars(18, peeked) && CharsMatch(peeked, "@sourceMappingURL=")) {
+        skipChars(18);
+        tokenbuf.clear();
+
+        jschar c;
+        while (!IsSpaceOrBOM2((c = getChar())) &&
+               ((char) c) != '\0' &&
+               ((char) c) != EOF)
+            tokenbuf.append(c);
+
+        if (tokenbuf.empty())
+            /* The source map's URL was missing, but not quite an exception that
+             * we should stop and drop everything for, though. */
+            return true;
+
+        int len = tokenbuf.length();
+
+        if (sourceMap)
+            cx->free_(sourceMap);
+        sourceMap = (jschar *) cx->malloc_(sizeof(jschar) * (len + 1));
+        if (!sourceMap)
+            return false;
+
+        for (int i = 0; i < len; i++)
+            sourceMap[i] = tokenbuf[i];
+        sourceMap[len] = '\0';
+    }
+    return true;
+}
+
 Token *
 TokenStream::newToken(ptrdiff_t adjust)
 {
@@ -1254,7 +1302,7 @@ bool
 TokenStream::putIdentInTokenbuf(const jschar *identStart)
 {
     int32 c, qc;
-    const jschar *tmp = userbuf.addressOfNextRawChar(); 
+    const jschar *tmp = userbuf.addressOfNextRawChar();
     userbuf.setAddressOfNextRawChar(identStart);
 
     tokenbuf.clear();
@@ -1483,7 +1531,7 @@ TokenStream::getTokenInternal()
             }
         }
 
-        /* 
+        /*
          * Identifiers containing no Unicode escapes can be atomized directly
          * from userbuf.  The rest must have the escapes converted via
          * tokenbuf before atomizing.
@@ -1681,7 +1729,7 @@ TokenStream::getTokenInternal()
             goto error;
         }
 
-        /* 
+        /*
          * Unlike identifiers and strings, numbers cannot contain escaped
          * chars, so we don't need to use tokenbuf.  Instead we can just
          * convert the jschars in userbuf directly to the numeric value.
@@ -1899,6 +1947,9 @@ TokenStream::getTokenInternal()
             if (cx->hasAtLineOption() && !getAtLine())
                 goto error;
 
+            if (!getAtSourceMappingURL())
+                goto error;
+
   skipline:
             /* Optimize line skipping if we are not in an HTML comment. */
             if (flags & TSF_IN_HTML_COMMENT) {

js/src/jsscan.h

@@ -22,6 +22,7 @@
  * the Initial Developer. All Rights Reserved.
  *
  * Contributor(s):
+ *   Nick Fitzgerald <nfitzgerald@mozilla.com>
  *
  * Alternatively, the contents of this file may be used under the terms of
  * either of the GNU General Public License Version 2 or later (the "GPL"),
@@ -485,6 +486,14 @@ class TokenStream
         return matchToken(tt);
     }
 
+    /*
+     * Give up responsibility for managing the sourceMap filename's memory.
+     */
+    const jschar *releaseSourceMap() {
+        const jschar* sm = sourceMap;
+        sourceMap = NULL;
+        return sm;
+    }
 
   private:
     /*
@@ -589,6 +598,7 @@ class TokenStream
     bool matchUnicodeEscapeIdent(int32 *c);
     bool peekChars(intN n, jschar *cp);
     bool getAtLine();
+    bool getAtSourceMappingURL();
 
     bool getXMLEntity();
     bool getXMLTextOrTag(TokenKind *ttp, Token **tpp);
@@ -626,6 +636,7 @@ class TokenStream
     const jschar        *prevLinebase;  /* start of previous line;  NULL if on the first line */
     TokenBuf            userbuf;        /* user input buffer */
     const char          *filename;      /* input filename or null */
+    jschar              *sourceMap;     /* source map's filename or null */
     void                *listenerTSData;/* listener data for this TokenStream */
     CharBuffer          tokenbuf;       /* current token string buffer */
     int8                oneCharTokens[128];  /* table of one-char tokens */

js/src/jsscript.cpp

@@ -23,6 +23,7 @@
  * the Initial Developer. All Rights Reserved.
  *
  * Contributor(s):
+ *   Nick Fitzgerald <nfitzgerald@mozilla.com>
  *
  * Alternatively, the contents of this file may be used under the terms of
  * either of the GNU General Public License Version 2 or later (the "GPL"),
@@ -1190,6 +1191,8 @@ JSScript::NewScriptFromCG(JSContext *cx, JSCodeGenerator *cg)
     if (script->principals)
         JSPRINCIPALS_HOLD(cx, script->principals);
 
+    script->sourceMap = (jschar *) cg->parser->tokenStream.releaseSourceMap();
+
     if (!js_FinishTakingSrcNotes(cx, cg, script->notes()))
         goto bad;
     if (cg->ntrynotes != 0)
@@ -1402,6 +1405,9 @@ DestroyScript(JSContext *cx, JSScript *script, JSObject *owner)
 
     script->pcCounters.destroy(cx);
 
+    if (script->sourceMap)
+        cx->free_(script->sourceMap);
+
     memset(script, JS_FREE_PATTERN, script->totalSize());
     cx->free_(script);
 }

js/src/jsscript.h

@@ -505,6 +505,7 @@ struct JSScript {
     js::Bindings    bindings;   /* names of top-level variables in this script
                                    (and arguments if this is a function script) */
     JSPrincipals    *principals;/* principals for this script */
+    jschar          *sourceMap; /* source map file or null */
 
     JSObject        *ownerObject;