Data: improve stripped log file loading performance

A ~9% improvement for files without colors. This now slightly outperforms the
code before color support was added.

1 files changed, 17 insertions, 7 deletions

diff --git a/GstDebugViewer/Data.py b/GstDebugViewer/Data.py
index b989a53..2261645 100644
--- a/GstDebugViewer/Data.py
+++ b/GstDebugViewer/Data.py
@@ -294,10 +294,14 @@ class LineCache (Producer):
                        "I" : debug_level_info, "W" : debug_level_warning,
                        "E" : debug_level_error, " " : debug_level_none}
         ANSI = "(?:\x1b\\[[0-9;]*m)?"
-        rexp = re.compile (r"\d:\d\d:\d\d\.\d+ " + ANSI +
-                           r" *\d+" + ANSI +
-                           r" +0x[0-9a-f]+ +" + ANSI +
-                           r"([TFLDIEW ])")
+        ANSI_PATTERN = (r"\d:\d\d:\d\d\.\d+ " + ANSI +
+                        r" *\d+" + ANSI +
+                        r" +0x[0-9a-f]+ +" + ANSI +
+                        r"([TFLDIEW ])")
+        BARE_PATTERN = ANSI_PATTERN.replace (ANSI, "")
+        rexp_bare = re.compile (BARE_PATTERN)
+        rexp_ansi = re.compile (ANSI_PATTERN)
+        rexp = rexp_bare
 
         # Moving attribute lookups out of the loop:
         readline = self.__fileobj.readline
@@ -323,11 +327,17 @@ class LineCache (Producer):
             line = readline ()
             if not line:
                 break
-            # if line[18] == "\x1b":
-            #     line = strip_escape (line)
             match = rexp_match (line)
             if match is None:
-                continue
+                if rexp is rexp_ansi or not "\x1b" in line:
+                    continue
+
+                match = rexp_ansi.match (line)
+                if match is None:
+                    continue
+                # Switch to slower ANSI parsing:
+                rexp = rexp_ansi
+                rexp_match = rexp.match
 
             # Timestamp is in the very beginning of the row, and can be sorted
             # by lexical comparison. That's why we don't bother parsing the