Cleanup do-gtest.py

[tberghammer]

Summary

• Add comments
• Refactor output manipulation (cleanup + minor bug fixes)
• Add better error reporting on test failure

[vharron]

https://www.youtube.com/watch?v=z1DzZ7oShl4

[tberghammer]

Committed as revision 226907.

gtest/do-gtest.py

 import subprocess
 import sys
 
-# Wrapping this rather than os.devnull since os.devnull does not seeem to implement 'write'.
+# Wrapping this rather than os.devnull since os.devnull does not seem to implement 'write'.
 class NullWriter(object):
     def write (self, *args):
         pass

     def close (self, *args):
         pass
 
+# Find all "Makefile"-s in the current directory.
 def find_makefile_dirs():
     makefile_dirs = []
     for root, dirs, files in os.walk("."):

                 makefile_dirs.append(root)
     return makefile_dirs
 
+# Test if line starts with <file name>:<line number> pattern
 _TESTDIR_RELATIVE_REGEX = re.compile(r"^([^/:]+:\d+:)")
-_COMBINER_TERMINATION_REGEX = re.compile(r"^.+FAILED.+$")
 
-def filter_run_line(sub_expr, line):
-    return _TESTDIR_RELATIVE_REGEX.subn(sub_expr, line)
+# Test if the line starts with the string "[ FAILED ]" (whitespace
+# independent) what displayed on the end of a failed test case
+_COMBINER_TERMINATION_REGEX = re.compile(r"^\[ *FAILED *\]")
 
+# Prepends directory before each file name in line matching the regular
+# expression "_TESTDIR_RELATIVE_REGEX" and returns the new value of line and the
+# number of file names modified as a tuple.
+def expand_file_name(directory, line):
+    return _TESTDIR_RELATIVE_REGEX.subn(directory + r"/\1", line)
+
+# Combine the failure report information from the output of gtest into a
+# single line for better displaying inside IDEs
 def line_combine_printer(file, previous_data, new_line_subn_result):
-    (accumulated_line, combine_lines_left) = previous_data
     (incoming_line, sub_match_count) = new_line_subn_result
 
     if sub_match_count > 0:
-        # New line was a match.  Don't print yet, start an accumulation.
-        if len(accumulated_line) > 0:
-            # Flush anything previously there.
-            print(accumulated_line, file=file)
-        return (incoming_line + ": ", 3)
+        # New line was a match for a file name. It means is the first line of
+        # a failure report. Don't print yet, start an accumulation for more
+        # info about the failure.
+        if len(previous_data) > 0:
+            # Flush anything previously accumulated (most likely part of the
+            # previous failure report).
+            print(previous_data, file=file)
+        return incoming_line + ": "
     else:
-        # If we're combining and incoming is a "[  FAILED ]" line, we've gone too far on a combine.
-        if (len(accumulated_line) > 0) and _COMBINER_TERMINATION_REGEX.match(incoming_line):
-            # Stop the combine.
-            print(accumulated_line, file=file)
+        # If we're combining and incoming is a "[ FAILED ]" line then we have
+        # to stop combining now.
+        if (len(previous_data) > 0) and _COMBINER_TERMINATION_REGEX.match(incoming_line):
+            # Stop the combine and print out its data and the FAIL line also.
+            print(previous_data, file=file)
             print(incoming_line, file=file)
-            return ("", 0)
+            return ""
 
-        if len(accumulated_line) > 0:
-            if accumulated_line[-2:] != ": ":
-                # Need to add a comma
-                new_line = accumulated_line + ", " + incoming_line
+        if len(previous_data) > 0:
+            # Previous data is available what means we are currently
+            # accumulating a failure report. Append this line to it.
+            if len(previous_data) >= 2 and previous_data[-2:] != ": ":
+                return previous_data + ", " + incoming_line
             else:
-                new_line = accumulated_line + incoming_line
-        else:
-            new_line = incoming_line
-
-        remaining_count = combine_lines_left - 1
-        if remaining_count > 0:
-            return (new_line, remaining_count)
+                return previous_data + incoming_line
         else:
-            # Time to write it out.
-            print(new_line, file=file)
-            return ("", 0)
+            # No previous data and don't have to start new accumulation. Just
+            # print the incoming line if it is not empty.
+            if len(incoming_line) > 0:
+                print(incoming_line, file=file)
+            return ""
 
 def call_make(makefile_dir, extra_args=None, stdout=sys.stdout, stderr=sys.stderr):
     command = ["make", "-C", makefile_dir]
     if extra_args:
         command.extend(extra_args)
 
-    # Replace the matched no-directory filename with one where the makefile directory is prepended.
-    sub_expr = makefile_dir + r"/\1";
-
+    # Execute make as a new subprocess
     proc = subprocess.Popen(command, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
 
-    stdout_data = ("", 0)
-    stderr_data = ("", 0)
+    stdout_data, stderr_data = "", ""
 
     while True:
         reads = [proc.stdout.fileno(), proc.stderr.fileno()]
         select_result = select.select(reads, [], [])
 
+        # Copy the currently available output from make to the standard output
+        # streams (stdout or stderr)
         for fd in select_result[0]:
             if fd == proc.stdout.fileno():
                 line = proc.stdout.readline()
-                stdout_data = line_combine_printer(stdout, stdout_data, filter_run_line(sub_expr, line.rstrip()))
+                stdout_data = line_combine_printer(stdout, stdout_data, expand_file_name(makefile_dir, line.rstrip()))
             elif fd == proc.stderr.fileno():
                 line = proc.stderr.readline()
-                stderr_data = line_combine_printer(stderr, stderr_data, filter_run_line(sub_expr, line.rstrip()))
+                stderr_data = line_combine_printer(stderr, stderr_data, expand_file_name(makefile_dir, line.rstrip()))
 
         proc_retval = proc.poll()
         if proc_retval != None:
-            # Process stopped.  Drain output before finishing up.
+            # Process stopped. Drain output before finishing up.
 
             # Drain stdout.
             while True:
                 line = proc.stdout.readline()
                 if line and len(line) > 0:
-                    stdout_data = line_combine_printer(stdout, stdout_data, filter_run_line(sub_expr, line.rstrip()))
+                    stdout_data = line_combine_printer(stdout, stdout_data, expand_file_name(makefile_dir, line.rstrip()))
                 else:
                     break
 

             while True:
                 line = proc.stderr.readline()
                 if line and len(line) > 0:
-                    stderr_data = line_combine_printer(stderr, stderr_data, filter_run_line(sub_expr, line.rstrip()))
+                    stderr_data = line_combine_printer(stderr, stderr_data, expand_file_name(makefile_dir, line.rstrip()))
                 else:
                     break
 

         retval = call_make(makefile_dir)
         # Remember any errors that happen here.
         if retval != 0:
+            print()
+            print("-" * 80)
+            print("Tests failed for Makefile in directory: %s" % makefile_dir)
+            print("-" * 80)
+            print()
             global_retval = retval
 
     # Now clean
     call_make(makefile_dir, ['clean'], stdout=NullWriter(), stderr=NullWriter())
-        
+if global_retval == 0:
+    print()
+    print("========================")
+    print("| All tests are PASSED |")
+    print("========================")
+else:
+    print()
+    print("=========================================================")
+    print("| Some of the test cases are FAILED with return code: %d |" % global_retval)
+    print("=========================================================")
 sys.exit(global_retval)