[PATCH 3 of 3 v2] filemerge: exclude some markup languages from conflict marker detection

[Gregory Szorc]

# HG changeset patch
# User Gregory Szorc <gregory.szorc at gmail.com>
# Date 1409470817 -7200
#      Sun Aug 31 09:40:17 2014 +0200
# Node ID ab2e712ecf4e79a59c7985359b00d21d0d39cfd6
# Parent  35c1d268bbd092ffb15b85605b4f5d36c3d08986
filemerge: exclude some markup languages from conflict marker detection

Detection of conflict markers looks for the '=======' string, which may
occur in markup languages such as markdown and restructured text.
We omit this part of conflict marker detection for these files.

diff --git a/mercurial/filemerge.py b/mercurial/filemerge.py
--- a/mercurial/filemerge.py
+++ b/mercurial/filemerge.py
@@ -464,11 +464,25 @@ def filemerge(repo, mynode, orig, fcd, f
     util.unlink(b)
     util.unlink(c)
     return r
 
+_includeequals = (
+    '.markdown',
+    '.md',
+    '.rst',
+)
+
 def hasconflictmarkers(fctx):
     """Whether data from a filecontext has conflict markers."""
-    return re.search("^(<<<<<<< .*|=======|>>>>>>> .*)$", fctx.data(),
-                     re.MULTILINE)
+    path = fctx.path()
+    regexp = '^(<<<<<<< .*|>>>>>>> .*'
+    # Some files commonly contain "=======". We try to avoid false positives.
+    for suffix in _includeequals:
+        if path.endswith(suffix):
+            regexp += '|======='
+            break
+    regexp += ')$'
+
+    return re.search(regexp, fctx.data(), re.MULTILINE)
 
 # tell hggettext to extract docstrings from these functions:
 i18nfunctions = internals.values()
diff --git a/tests/test-resolve.t b/tests/test-resolve.t
--- a/tests/test-resolve.t
+++ b/tests/test-resolve.t
@@ -81,4 +81,45 @@ conflict markers in file marked as resol
   > EOF
   $ hg resolve -m file
   (file appears to contain conflict markers; did you intend to mark as resolved?)
   (no more unresolved files)
+
+  $ cd ..
+
+conflict marker warning is ignored for files with those patterns
+
+  $ hg init markdown
+  $ cd markdown
+  $ cat >> readme.md << EOF
+  > == Index
+  > Hello
+  > ========= Another section
+  > more content
+  > EOF
+  $ cat >> readme.rst << EOF
+  > ========
+  > My Index
+  > ========
+  > EOF
+  $ hg commit -A -m 'add readme'
+  adding readme.md
+  adding readme.rst
+  $ echo 'even more content' >> readme.md
+  $ echo 'even more content' >> readme.rst
+  $ hg commit -m 'append readme'
+
+  $ hg up -r 0
+  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  $ echo 'alternative content' >> readme.md
+  $ echo 'alternative content' >> readme.rst
+  $ hg commit -m 'other append'
+  created new head
+
+  $ hg merge --tool=internal:fail
+  0 files updated, 0 files merged, 0 files removed, 2 files unresolved
+  use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon
+  [1]
+
+  $ hg resolve -m
+  (no more unresolved files)
+
+  $ cd ..