bug 2831: Allow appending Help text to Options Output

http://scons.tigris.org/issues/show_bug.cgi?id=2831

In order to append, rather than clobber Help() generated
text, use Help("my message", append=True)

The append argument is only respected on the first call to this
method as it operates on global data.

4 files changed, 20 insertions, 5 deletions

diff --git a/src/CHANGES.txt b/src/CHANGES.txt
index 55b48a5..cd98f12 100644
--- a/src/CHANGES.txt
+++ b/src/CHANGES.txt
@@ -6,6 +6,9 @@
 
 RELEASE  VERSION/DATE TO BE FILLED IN LATER
 
+  From William Roberts:
+    - Fix bug 2831 and allow Help() text to be appended to AddOption() help.
+
   From Russel Winder:
     - Add support for f08 file extensions for Fortran 2008 code.
 
diff --git a/src/engine/SCons/Script/Main.py b/src/engine/SCons/Script/Main.py
index c7a9d27..4ccd2b3 100644
--- a/src/engine/SCons/Script/Main.py
+++ b/src/engine/SCons/Script/Main.py
@@ -484,6 +484,9 @@ def GetOption(name):
 def SetOption(name, value):
     return OptionsParser.values.set_option(name, value)
 
+def PrintHelp(file=None):
+    OptionsParser.print_help(file=file)
+
 #
 class Stats(object):
     def __init__(self):
diff --git a/src/engine/SCons/Script/SConscript.py b/src/engine/SCons/Script/SConscript.py
index f4a7f07..3502534 100644
--- a/src/engine/SCons/Script/SConscript.py
+++ b/src/engine/SCons/Script/SConscript.py
@@ -499,9 +499,9 @@ class SConsEnvironment(SCons.Environment.Base):
         name = self.subst(name)
         return SCons.Script.Main.GetOption(name)
 
-    def Help(self, text):
+    def Help(self, text, append=False):
         text = self.subst(text, raw=1)
-        SCons.Script.HelpFunction(text)
+        SCons.Script.HelpFunction(text, append=append)
 
     def Import(self, *vars):
         try:
diff --git a/src/engine/SCons/Script/__init__.py b/src/engine/SCons/Script/__init__.py
index bb7b632..a9d7708 100644
--- a/src/engine/SCons/Script/__init__.py
+++ b/src/engine/SCons/Script/__init__.py
@@ -41,6 +41,7 @@ start_time = time.time()
 
 import collections
 import os
+import StringIO
 import sys
 
 # Special chicken-and-egg handling of the "--debug=memoizer" flag:
@@ -107,6 +108,7 @@ QuestionTask            = Main.QuestionTask
 #SConscriptSettableOptions = Main.SConscriptSettableOptions
 
 AddOption               = Main.AddOption
+PrintHelp               = Main.PrintHelp
 GetOption               = Main.GetOption
 SetOption               = Main.SetOption
 Progress                = Main.Progress
@@ -258,10 +260,17 @@ def _Set_Default_Targets(env, tlist):
 #
 help_text = None
 
-def HelpFunction(text):
+def HelpFunction(text, append=False):
     global help_text
-    if SCons.Script.help_text is None:
-        SCons.Script.help_text = text
+    if help_text is None:
+        if append:
+            s = StringIO.StringIO()
+            PrintHelp(s)  
+            help_text = s.getvalue()
+            s.close()
+        else:
+            help_text = ""       
+        help_text = help_text + "\nLocal Build Variables:\n" + text
     else:
         help_text = help_text + text