cover other type of subber and add test

2 files changed, 31 insertions, 2 deletions

diff --git a/SCons/Subst.py b/SCons/Subst.py
index 29698d5..fbb89b3 100644
--- a/SCons/Subst.py
+++ b/SCons/Subst.py
@@ -591,12 +591,13 @@ class ListSubber(collections.UserList):
                 self.substitute(a, lvars, 1)
                 self.next_word()
         elif callable(s):
-            try:
+            if (s and
+                set(signature(s).parameters.keys()) == set(['target', 'source', 'env', 'for_signature'])):
                 s = s(target=lvars['TARGETS'],
                      source=lvars['SOURCES'],
                      env=self.env,
                      for_signature=(self.mode != SUBST_CMD))
-            except TypeError:
+            else:
                 # This probably indicates that it's a callable
                 # object that doesn't match our calling arguments
                 # (like an Action).
diff --git a/test/Subst/TypeError.py b/test/Subst/TypeError.py
index 628db2f..b288961 100644
--- a/test/Subst/TypeError.py
+++ b/test/Subst/TypeError.py
@@ -85,8 +85,36 @@ expect = expect_build % (r' \[foo\.bar\]', r'\$\{func\(1\)\}')
 
 test.run(status=2, stderr=expect)
 
+# callable exceptions:
+test.write('foo.c', """\
+#include <stdio.h>
+#include <stdlib.h>
+int
+main(int argc, char *argv[])
+{
+        argv[argc++] = "--";
+        printf("foo.c");
+        exit (0);
+}
+""")
+
+test.write('SConstruct', """\
 
+class TestCallable(object):
+    def __init__(self, thing, makePathsRelative = True, debug = False):
+        pass
+    def __call__(self, target, source, env, for_signature):
+       raise TypeError("User callable exception")
+
+env = Environment()
+env["TESTCLASS"] = TestCallable
+env["CCCOM"] = "$CC $_CCCOMCOM $CCFLAGS -o ${TESTCLASS('$TARGET')} -c ${TESTCLASS('$SOURCES')}"
+
+env.Program(target='foo', source='foo.c')
+""")
 
+test.run(status=2, stderr=r'.*TypeError\s:\sUser\scallable\sexception.*')
+print(test.stdout())
 test.pass_test()
 
 # Local Variables: