# HG changeset patch
# User mpm@selenic.com
# Date 2005-06-08 18:47:10
# Node ID 777e388c06d61ef26f7f60ab3784d17bbf0d164b
# Parent  79279550c8ffa4cf556e403e9855bc1ed28b8bdd

unidiff: handle empty diffs more gracefully

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unidiff: handle empty diffs more gracefully

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diff --git a/mercurial/mdiff.py b/mercurial/mdiff.py
--- a/mercurial/mdiff.py
+++ b/mercurial/mdiff.py
@@ -27,6 +27,7 @@ def unidiff(a, ad, b, bd, fn):
         a = a.splitlines(1)
         b = b.splitlines(1)
         l = list(difflib.unified_diff(a, b, "a/" + fn, "b/" + fn))
+        if not l: return ""
         # difflib uses a space, rather than a tab
         l[0] = l[0][:-2] + "\t" + ad + "\n"
         l[1] = l[1][:-2] + "\t" + bd + "\n"