Move autogeneration of PATH-based variables from Environment initialization to variable interpolation.

1 files changed, 59 insertions, 0 deletions

diff --git a/src/engine/SCons/Util.py b/src/engine/SCons/Util.py
index 9108f14..b8286d1 100644
--- a/src/engine/SCons/Util.py
+++ b/src/engine/SCons/Util.py
@@ -254,3 +254,62 @@ def find_files(filenames, paths,
                 pass
 
     return nodes
+
+
+
+# See the documentation for the __autogenerate() method
+# for an explanation of this variable...
+AUTO_GEN_VARS = ( ( '_LIBFLAGS',
+                    'LIBS',
+                    'LIBLINKPREFIX',
+                    'LIBLINKSUFFIX' ),
+                  ( '_LIBDIRFLAGS',
+                    'LIBPATH',
+                    'LIBDIRPREFIX',
+                    'LIBDIRSUFFIX' ),
+                  ( '_INCFLAGS',
+                    'CPPPATH',
+                    'INCPREFIX',
+                    'INCSUFFIX' ) )
+
+def autogenerate(dict):
+    """Autogenerate the "interpolated" environment variables.
+    We read a static structure that tells us how.  AUTO_GEN_VARS
+    is a tuple of tuples.  Each inner tuple has four elements,
+    each strings referring to an environment variable, and describing
+    how to autogenerate a particular variable.  The elements are:
+
+    0 - The variable to generate
+    1 - The "source" variable, usually a list
+    2 - The "prefix" variable
+    3 - The "suffix" variable
+
+    The autogenerated variable is a list, consisting of every
+    element of the source list, or a single element if the source
+    is a string, with the prefix and suffix
+    concatenated."""
+
+    for strVarAuto, strSrc, strPref, strSuff, in AUTO_GEN_VARS:
+        if dict.has_key(strSrc):
+            src_var = dict[strSrc]
+            if type(src_var) is types.ListType or \
+               isinstance(src_var, UserList):
+                src_var = map(str, src_var)
+            else:
+                src_var = [ str(src_var), ]
+        else:
+            src_var = []
+
+        try:
+            prefix = str(dict[strPref])
+        except KeyError:
+            prefix=''
+
+        try:
+            suffix = str(dict[strSuff])
+        except KeyError:
+            suffix =''
+
+        dict[strVarAuto] = map(lambda x, suff=suffix, pref=prefix: \
+                               pref + os.path.normpath(str(x)) + suff,
+                               src_var)