Bug 770182 Warn when preprocessing unnecessarily r=bsmedberg

config/JarMaker.py

@@ -370,6 +370,7 @@ class JarMaker(object):
           pp.setMarker('%')
         pp.out = outf
         pp.do_include(inf)
+        pp.warnUnused(realsrc)
         outf.close()
         inf.close()
         return

config/Preprocessor.py

@@ -41,6 +41,7 @@ class Preprocessor:
                 'LINE': 0,
                 'DIRECTORY': os.path.abspath('.')}.iteritems():
       self.context[k] = v
+    self.actionLevel = 0
     self.disableLevel = 0
     # ifStates can be
     #  0: hadTrue
@@ -74,6 +75,13 @@ class Preprocessor:
     self.LE = '\n'
     self.varsubst = re.compile('@(?P<VAR>\w+)@', re.U)
   
+  def warnUnused(self, file):
+    if self.actionLevel == 0:
+      sys.stderr.write('%s: WARNING: no preprocessor directives found\n' % file)
+    elif self.actionLevel == 1:
+      sys.stderr.write('%s: WARNING: no useful preprocessor directives found\n' % file)
+    pass
+
   def setLineEndings(self, aLE):
     """
     Set the line endings to be used for output.
@@ -135,8 +143,10 @@ class Preprocessor:
     if defaultToStdin and len(args) == 0:
       args = [sys.stdin]
     includes.extend(args)
-    for f in includes:
-      self.do_include(f, False)
+    if includes:
+      for f in includes:
+        self.do_include(f, False)
+      self.warnUnused(f)
     pass
 
   def getCommandLineParser(self, unescapeDefines = False):
@@ -186,6 +196,8 @@ class Preprocessor:
     """
     Handle a single line of input (internal).
     """
+    if self.actionLevel == 0 and self.comment.match(aLine):
+      self.actionLevel = 1
     m = self.instruction.match(aLine)
     if m:
       args = None
@@ -199,6 +211,8 @@ class Preprocessor:
       level, cmd = self.cmds[cmd]
       if (level >= self.disableLevel):
         cmd(args)
+      if cmd != 'literal':
+        self.actionLevel = 2
     elif self.disableLevel == 0 and not self.comment.match(aLine):
       self.write(aLine)
     pass

js/src/config/Preprocessor.py

@@ -41,6 +41,7 @@ class Preprocessor:
                 'LINE': 0,
                 'DIRECTORY': os.path.abspath('.')}.iteritems():
       self.context[k] = v
+    self.actionLevel = 0
     self.disableLevel = 0
     # ifStates can be
     #  0: hadTrue
@@ -74,6 +75,13 @@ class Preprocessor:
     self.LE = '\n'
     self.varsubst = re.compile('@(?P<VAR>\w+)@', re.U)
   
+  def warnUnused(self, file):
+    if self.actionLevel == 0:
+      sys.stderr.write('%s: WARNING: no preprocessor directives found\n' % file)
+    elif self.actionLevel == 1:
+      sys.stderr.write('%s: WARNING: no useful preprocessor directives found\n' % file)
+    pass
+
   def setLineEndings(self, aLE):
     """
     Set the line endings to be used for output.
@@ -135,8 +143,10 @@ class Preprocessor:
     if defaultToStdin and len(args) == 0:
       args = [sys.stdin]
     includes.extend(args)
-    for f in includes:
-      self.do_include(f, False)
+    if includes:
+      for f in includes:
+        self.do_include(f, False)
+      self.warnUnused(f)
     pass
 
   def getCommandLineParser(self, unescapeDefines = False):
@@ -186,6 +196,8 @@ class Preprocessor:
     """
     Handle a single line of input (internal).
     """
+    if self.actionLevel == 0 and self.comment.match(aLine):
+      self.actionLevel = 1
     m = self.instruction.match(aLine)
     if m:
       args = None
@@ -199,6 +211,8 @@ class Preprocessor:
       level, cmd = self.cmds[cmd]
       if (level >= self.disableLevel):
         cmd(args)
+      if cmd != 'literal':
+        self.actionLevel = 2
     elif self.disableLevel == 0 and not self.comment.match(aLine):
       self.write(aLine)
     pass