Allow disabling of escape code stripping, fix #1475

Don't strip colors when CLICOLOR_FORCE is set to a non-zero value. This
environment variable is also used by CMake's Make back-end.

3 files changed, 20 insertions, 6 deletions

diff --git a/misc/output_test.py b/misc/output_test.py
index 6a5b635..878de19 100755
--- a/misc/output_test.py
+++ b/misc/output_test.py
@@ -11,11 +11,14 @@ import sys
 import tempfile
 import unittest
 
-def run(build_ninja, flags='', pipe=False):
-    env = dict(os.environ)
-    if 'NINJA_STATUS' in env:
-        del env['NINJA_STATUS']
-    env['TERM'] = ''
+default_env = dict(os.environ)
+if 'NINJA_STATUS' in default_env:
+    del default_env['NINJA_STATUS']
+if 'CLICOLOR_FORCE' in default_env:
+    del default_env['CLICOLOR_FORCE']
+default_env['TERM'] = ''
+
+def run(build_ninja, flags='', pipe=False, env=default_env):
     with tempfile.NamedTemporaryFile('w') as f:
         f.write(build_ninja)
         f.flush()
@@ -84,5 +87,13 @@ red
 red
 ''')
 
+        # CLICOLOR_FORCE=1 can be used to disable escape code stripping.
+        env = default_env.copy()
+        env['CLICOLOR_FORCE'] = '1'
+        self.assertEqual(run(print_red, pipe=True, env=env),
+'''[1/1] echo a
+\x1b[31mred\x1b[0m
+''')
+
 if __name__ == '__main__':
     unittest.main()
diff --git a/src/build.cc b/src/build.cc
index 6b33024..ed219fd 100644
--- a/src/build.cc
+++ b/src/build.cc
@@ -154,7 +154,6 @@ void BuildStatus::BuildEdgeFinished(Edge* edge,
     // (Launching subprocesses in pseudo ttys doesn't work because there are
     // only a few hundred available on some systems, and ninja can launch
     // thousands of parallel compile commands.)
-    // TODO: There should be a flag to disable escape code stripping.
     string final_output;
     if (!printer_.supports_color())
       final_output = StripAnsiEscapeCodes(output);
diff --git a/src/line_printer.cc b/src/line_printer.cc
index a3a551e..6effca6 100644
--- a/src/line_printer.cc
+++ b/src/line_printer.cc
@@ -42,6 +42,10 @@ LinePrinter::LinePrinter() : have_blank_line_(true), console_locked_(false) {
   smart_terminal_ = GetConsoleScreenBufferInfo(console_, &csbi);
 #endif
   supports_color_ = smart_terminal_;
+  if (!supports_color_) {
+    const char* clicolor_force = getenv("CLICOLOR_FORCE");
+    supports_color_ = clicolor_force && string(clicolor_force) != "0";
+  }
 }
 
 void LinePrinter::Print(string to_print, LineType type) {