Merge fixes to run from source

2 files changed, 21 insertions, 11 deletions

diff --git a/src/CHANGES.txt b/src/CHANGES.txt
index 52d8604..baeda64 100644
--- a/src/CHANGES.txt
+++ b/src/CHANGES.txt
@@ -57,10 +57,16 @@ RELEASE 2.3.1.alpha.yyyymmdd - NEW DATE WILL BE INSERTED HERE
     - Test harness: fail_test() can now print a message to help debugging.
 
   From Anatoly Techtonik:
-    - Require rpmbuild when building SCons package.
-    - Print full stack on certain errors, for debugging.
-    - Improve documentation for Textfile builder.
-
+    - Several improvements for running scons.py from source:
+      * engine files form source directory take priority over all other
+        importable versions
+      * message about scons.py running from source is removed to fix tests
+        that were failing because of this extra line in the output
+      * error message when SCons import fails now lists lookup paths
+    - Fixed rpmbuild requirement for building SCons .rpm package.
+    - Improved Debug tools to return full caller stack (PR#66).
+    - Improved documentation for Textfile builder.
+    
   From William Deegan:
     - VS2012 & VS2010 Resolve initialization issues by adding path to reg.exe
       in shell used to run batch files.
diff --git a/src/script/scons.py b/src/script/scons.py
index 46e6d2b..2c17cd8 100644
--- a/src/script/scons.py
+++ b/src/script/scons.py
@@ -85,6 +85,11 @@ scons_version = 'scons-%s' % __version__
 # preferred order of scons lookup paths
 prefs = []
 
+# - running from source takes priority (since 2.3.1)
+script_path = os.path.abspath(os.path.dirname(__file__))
+source_path = os.path.join(script_path, '..', 'engine')
+
+# - running from egg check
 try:
     import pkg_resources
 except ImportError:
@@ -171,7 +176,7 @@ else:
 libs.extend([os.path.join(x, scons_version) for x in prefs])
 libs.extend([os.path.join(x, 'scons') for x in prefs])
 
-sys.path = libs + sys.path
+sys.path = [source_path] + libs + sys.path
 
 ##############################################################################
 # END STANDARD SCons SCRIPT HEADER
@@ -181,12 +186,11 @@ if __name__ == "__main__":
     try:
         import SCons.Script
     except:
-        ROOT = os.path.join(os.path.abspath(os.path.dirname(__file__)), '..', 'engine')
-        if os.path.exists(ROOT):
-            sys.path += [ROOT]
-            print("SCons import failed. Trying to run from source directory")
-        import SCons.Script
-  
+        print("Import failed. Unable to find SCons files in:")
+        for path in [source_path] + libs:
+          print "  %s" % path
+        raise
+
     # this does all the work, and calls sys.exit
     # with the proper exit status when done.
     SCons.Script.main()