1 files changed, 127 insertions, 0 deletions
diff --git a/python/helpers/pydev/pydevd_dont_trace.py b/python/helpers/pydev/pydevd_dont_trace.py
new file mode 100644
index 000000000000..2d5ad959f7b0
--- /dev/null
+++ b/python/helpers/pydev/pydevd_dont_trace.py
@@ -0,0 +1,127 @@
+'''
+Support for a tag that allows skipping over functions while debugging.
+'''
+import linecache
+import re
+from pydevd_constants import DictContains
+
+# To suppress tracing a method, add the tag @DontTrace
+# to a comment either preceding or on the same line as
+# the method definition
+#
+# E.g.:
+# #@DontTrace
+# def test1():
+#     pass
+#
+#  ... or ...
+#
+# def test2(): #@DontTrace
+#     pass
+DONT_TRACE_TAG = '@DontTrace'
+
+# Regular expression to match a decorator (at the beginning
+# of a line).
+RE_DECORATOR = re.compile(r'^\s*@')
+
+# Mapping from code object to bool.
+# If the key exists, the value is the cached result of should_trace_hook
+_filename_to_ignored_lines = {}
+
+def default_should_trace_hook(frame, filename):
+    '''
+    Return True if this frame should be traced, False if tracing should be blocked.
+    '''
+    # First, check whether this code object has a cached value
+    ignored_lines = _filename_to_ignored_lines.get(filename)
+    if ignored_lines is None:
+        # Now, look up that line of code and check for a @DontTrace
+        # preceding or on the same line as the method.
+        # E.g.:
+        # #@DontTrace
+        # def test():
+        #     pass
+        #  ... or ...
+        # def test(): #@DontTrace
+        #     pass
+        ignored_lines = {}
+        lines = linecache.getlines(filename)
+        i_line = 0  # Could use enumerate, but not there on all versions...
+        for line in lines:
+            j = line.find('#')
+            if j >= 0:
+                comment = line[j:]
+                if DONT_TRACE_TAG in comment:
+                    ignored_lines[i_line] = 1
+                    
+                    #Note: when it's found in the comment, mark it up and down for the decorator lines found.
+                    k = i_line - 1
+                    while k >= 0:
+                        if RE_DECORATOR.match(lines[k]):
+                            ignored_lines[k] = 1
+                            k -= 1
+                        else:
+                            break
+                        
+                    k = i_line + 1
+                    while k <= len(lines):
+                        if RE_DECORATOR.match(lines[k]):
+                            ignored_lines[k] = 1
+                            k += 1
+                        else:
+                            break
+                        
+            i_line += 1
+                    
+
+        _filename_to_ignored_lines[filename] = ignored_lines
+
+    func_line = frame.f_code.co_firstlineno - 1 # co_firstlineno is 1-based, so -1 is needed
+    return not (
+        DictContains(ignored_lines, func_line - 1) or #-1 to get line before method 
+        DictContains(ignored_lines, func_line)) #method line
+
+
+should_trace_hook = None
+
+
+def clear_trace_filter_cache():
+    '''
+    Clear the trace filter cache.
+    Call this after reloading.
+    '''
+    global should_trace_hook
+    try:
+        # Need to temporarily disable a hook because otherwise
+        # _filename_to_ignored_lines.clear() will never complete.
+        old_hook = should_trace_hook
+        should_trace_hook = None
+
+        # Clear the linecache
+        linecache.clearcache()
+        _filename_to_ignored_lines.clear()
+
+    finally:
+        should_trace_hook = old_hook
+
+
+def trace_filter(mode):
+    '''
+    Set the trace filter mode.
+
+    mode: Whether to enable the trace hook.
+      True: Trace filtering on (skipping methods tagged @DontTrace)
+      False: Trace filtering off (trace methods tagged @DontTrace)
+      None/default: Toggle trace filtering.
+    '''
+    global should_trace_hook
+    if mode is None:
+        mode = should_trace_hook is None
+
+    if mode:
+        should_trace_hook = default_should_trace_hook
+    else:
+        should_trace_hook = None
+
+    return mode
+