diff --git a/.gitattributes b/.gitattributes
new file mode 100644
index 00000000..facf16e4
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+++ b/.gitattributes
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+# Tests of static file handling assume unix-style line endings.
+tornado/test/static/*.txt text eol=lf
+tornado/test/static/dir/*.html text eol=lf
+tornado/test/templates/*.html text eol=lf