From 2914b27bda58c4fef415dcf634c5b1d41cf86ba3 Mon Sep 17 00:00:00 2001
From: stevenknight <stevenknight@fdb21ef1-2011-0410-befe-b5e4ea1792b1>
Date: Sun, 27 Jan 2002 15:20:33 +0000
Subject: [PATCH] Add a --debug=pdb option to run SCons under the Python
 debugger.

git-svn-id: http://scons.tigris.org/svn/scons/trunk@226 fdb21ef1-2011-0410-befe-b5e4ea1792b1
---
 doc/man/scons.1                     | 42 ++++++++++++++++++-----------
 src/CHANGES.txt                     |  2 ++
 src/engine/SCons/Script/__init__.py | 16 ++++++++++-
 3 files changed, 44 insertions(+), 16 deletions(-)

diff --git a/doc/man/scons.1 b/doc/man/scons.1
index cadc7b89..69da1005 100644
--- a/doc/man/scons.1
+++ b/doc/man/scons.1
@@ -31,7 +31,7 @@
 .RE
 .fi
 ..
-.TH SCONS 1 "December 2001"
+.TH SCONS 1 "January 2002"
 .SH NAME
 scons \- software constructor
 .SH SYNOPSIS
@@ -274,13 +274,25 @@ in the specified directory.)
 
 .TP
 .RI --debug= type
-Print debugging information durring the build process.
+Debug the build process.
 .I type
-specifies what type of of debugging information to print. Currently the
-only supported type is
-.I tree
-which causes the dependency tree to be printed after each top-level
-target is built.
+specifies what type of debugging:
+
+.TP
+.RI --debug=pdb
+Re-run SCons under the control of the
+.RI pdb
+Python debugger.
+The
+.RI --debug=pdb
+argument will be stripped from the command-line,
+but all other arguments will be passed in-order
+to the SCons invocation run by the debugger.
+
+.TP
+.RI --debug=tree
+Print the dependency tree
+after each top-level target is built.
 
 .TP
 -e, --environment-overrides
@@ -727,7 +739,7 @@ The list of directories that the C preprocessor will search for include
 directories. The C/C++ implicit dependency scanner will search these
 directories for include files. Don't explicitly put include directory
 arguments in CCFLAGS or CXXFLAGS because the result will be non-portable
-and the directories will not be searched by the depedency scanner. Note:
+and the directories will not be searched by the dependency scanner. Note:
 directory names in CPPPATH will be looked-up relative to the SConscript
 directory when they are used in a command. To force 
 .B scons
@@ -763,7 +775,7 @@ Note that, by default,
 .B scons
 does
 .I not
-propogate the environment in force when you
+propagate the environment in force when you
 execute
 .B scons
 to the commands used to build target files.
@@ -773,11 +785,11 @@ variables set at the time
 .B scons
 is invoked.
 
-If you want to propogate your
+If you want to propagate your
 environment variables
 to the commands executed
 to build target files,
-you must do so explictly:
+you must do so explicitly:
 
 .ES
 import os
@@ -785,7 +797,7 @@ env = Environment(ENV = os.environ)
 .EE
 
 .RS
-Note that you can choose only to propogate
+Note that you can choose only to propagate
 certain environment variables.
 A common example is
 the system
@@ -932,14 +944,14 @@ is usually safe, and is always more efficient than
 .RI Default( targets )
 This specifies a list of default targets. Default targets will be built by
 .B scons
-if no explicit targets are given on the comamnd line. Multiple targets can
+if no explicit targets are given on the command line. Multiple targets can
 be specified either as a space delimited string of target file names or as
-seperate arguments.
+separate arguments.
 Target names with white space may be be enclosed in an
 array to prevent the string from being split into
 separate file names.
 .BR Default ()
-will also accept the return value of any of the ccnstruction environment
+will also accept the return value of any of the construction environment
 builder methods.
 Example:
 
diff --git a/src/CHANGES.txt b/src/CHANGES.txt
index f3812417..05c4b81c 100644
--- a/src/CHANGES.txt
+++ b/src/CHANGES.txt
@@ -63,6 +63,8 @@ RELEASE 0.04 -
     and updating multiple targets in a single Task.  Simplify the
     interface between Task and Taskmaster.
 
+  - Add a --debug=pdb option to re-run SCons under the Python debugger.
+
   From Steve Leblanc:
 
   - Add var=value command-line arguments.
diff --git a/src/engine/SCons/Script/__init__.py b/src/engine/SCons/Script/__init__.py
index 12a22f49..0416b629 100644
--- a/src/engine/SCons/Script/__init__.py
+++ b/src/engine/SCons/Script/__init__.py
@@ -361,7 +361,21 @@ def options_init():
 
     def opt_debug(opt, arg):
         global print_tree
-        if arg == "tree":
+        if arg == "pdb":
+            if sys.platform == 'win32':
+                lib_dir = os.path.join(sys.exec_prefix, "lib")
+            else:
+                lib_dir = os.path.join(sys.exec_prefix,
+                                       "lib",
+                                       "python" + sys.version[0:3])
+            args = [ sys.executable, os.path.join(lib_dir, "pdb.py") ] + \
+                     filter(lambda x: x != "--debug=pdb", sys.argv)
+            if sys.platform == 'win32':
+                ret = os.spawnve(os.P_WAIT, cmd_interp, args, env)
+                sys.exit(ret)
+            else:
+                os.execvpe(args[0], args, os.environ)
+        elif arg == "tree":
             print_tree = 1
         else:
             sys.stderr.write("Warning:  %s is not a valid debug type\n"
-- 
2.26.2