From d32c57867238b0f960b11eb5692e102d595dc1de Mon Sep 17 00:00:00 2001
From: stevenknight <stevenknight@fdb21ef1-2011-0410-befe-b5e4ea1792b1>
Date: Wed, 23 Jan 2002 22:59:58 +0000
Subject: [PATCH] Provide a traceback if a Python-function builder throws an
 exception (Crain).

git-svn-id: http://scons.tigris.org/svn/scons/trunk@219 fdb21ef1-2011-0410-befe-b5e4ea1792b1
---
 src/engine/SCons/Node/NodeTests.py  | 20 ++++++++++++++++++++
 src/engine/SCons/Node/__init__.py   |  6 +++++-
 src/engine/SCons/Script/__init__.py |  3 +++
 test/build-errors.py                |  4 ++--
 test/exceptions.py                  | 17 ++++++++++++++---
 5 files changed, 44 insertions(+), 6 deletions(-)

diff --git a/src/engine/SCons/Node/NodeTests.py b/src/engine/SCons/Node/NodeTests.py
index 37b9f37d..10507679 100644
--- a/src/engine/SCons/Node/NodeTests.py
+++ b/src/engine/SCons/Node/NodeTests.py
@@ -60,6 +60,10 @@ class ExceptBuilder:
     def execute(self, **kw):
         raise SCons.Errors.BuildError
 
+class ExceptBuilder2:
+    def execute(self, **kw):
+        raise "foo"
+
 class Environment:
     def Dictionary(self, *args):
 	pass
@@ -91,6 +95,22 @@ class NodeTestCase(unittest.TestCase):
         else:
             raise TestFailed, "did not catch expected BuildError"
 
+        node = SCons.Node.Node()
+        node.builder_set(ExceptBuilder2())
+        node.env_set(Environment())
+        try:
+            node.build()
+        except SCons.Errors.BuildError, e:
+            # On a generic (non-BuildError) exception from a Builder,
+            # the Node should throw a BuildError exception with
+            # the args set to the exception value, type, and traceback.
+            assert len(e.args) == 3, `e.args`
+            assert e.args[0] == 'foo', e.args[0]
+            assert e.args[1] is None
+            assert type(e.args[2]) is type(sys.exc_traceback), e.args[2]
+        else:
+            raise TestFailed, "did not catch expected BuildError"
+
     def test_build(self):
 	"""Test building a node
 	"""
diff --git a/src/engine/SCons/Node/__init__.py b/src/engine/SCons/Node/__init__.py
index f2d379fe..c6418951 100644
--- a/src/engine/SCons/Node/__init__.py
+++ b/src/engine/SCons/Node/__init__.py
@@ -35,6 +35,7 @@ from SCons.Errors import BuildError
 import string
 import types
 import copy
+import sys
 
 # Node states
 #
@@ -77,7 +78,10 @@ class Node:
             stat = self.builder.execute(env = self.env.Dictionary(),
                                         target = self, source = self.sources)
         except:
-            raise BuildError(node = self, errstr = "Exception")
+            raise BuildError(self, "Exception",
+                             sys.exc_type,
+                             sys.exc_value,
+                             sys.exc_traceback)
         if stat:
             raise BuildError(node = self, errstr = "Error %d" % stat)
 
diff --git a/src/engine/SCons/Script/__init__.py b/src/engine/SCons/Script/__init__.py
index 1788fab2..acbd6c0b 100644
--- a/src/engine/SCons/Script/__init__.py
+++ b/src/engine/SCons/Script/__init__.py
@@ -76,6 +76,9 @@ class BuildTask(SCons.Taskmaster.Task):
                 self.target.build()
             except BuildError, e:
                 sys.stderr.write("scons: *** [%s] %s\n" % (e.node, e.errstr))
+                if e.errstr == 'Exception':
+                    traceback.print_exception(e.args[0], e.args[1],
+                                              e.args[2])
                 raise
 
     def executed(self):
diff --git a/test/build-errors.py b/test/build-errors.py
index 85456422..edd06b1c 100644
--- a/test/build-errors.py
+++ b/test/build-errors.py
@@ -90,7 +90,7 @@ test.description_set("Incorrect STDERR:\n%s\n" % test.stderr())
 if os.name == 'nt':
     errs = [
         bad_command,
-        unrecognized % (no_such_file, 'f2'),
+        unrecognized % (not_executable, 'f2'),
         unspecified % 'f2'
     ]
     test.fail_test(not test.stderr() in errs)
@@ -113,7 +113,7 @@ test.description_set("Incorrect STDERR:\n%s\n" % test.stderr())
 if os.name == 'nt':
     errs = [
         bad_command,
-        unrecognized % (no_such_file, 'f3'),
+        unrecognized % (test.workdir, 'f3'),
         unspecified % 'f3'
     ]
     test.fail_test(not test.stderr() in errs)
diff --git a/test/exceptions.py b/test/exceptions.py
index e67cec6d..8fc53483 100644
--- a/test/exceptions.py
+++ b/test/exceptions.py
@@ -27,8 +27,9 @@ __revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
 import os
 import sys
 import TestSCons
+import TestCmd
 
-test = TestSCons.TestSCons()
+test = TestSCons.TestSCons(match = TestCmd.match_re)
 
 test.write('SConstruct', """
 def func(source = None, target = None, env = None):
@@ -40,6 +41,16 @@ env.B(target = 'foo.out', source = 'foo.in')
 
 test.write('foo.in', "foo.in\n")
 
-test.run(arguments = "foo.out", stderr = "scons: *** [foo.out] Exception\n")
-
+test.run(arguments = "foo.out", stderr = """scons: \*\*\* \[foo.out\] Exception
+Traceback \((most recent call|innermost) last\):
+  File ".+", line \d+, in .+
+    .+
+  File ".+", line \d+, in .+
+    .+
+  File ".+", line \d+, in .+
+    .+
+  File "SConstruct", line 3, in func
+    raise "func exception"
+func exception
+""")
 test.pass_test()
-- 
2.26.2