--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/tests/test-extdata.t	Sun Oct 01 10:50:00 2017 +0100
@@ -0,0 +1,56 @@
+  $ hg init repo
+  $ cd repo
+  $ for n in 0 1 2 3; do
+  >   echo $n > $n
+  >   hg ci -qAm $n
+  > done
+
+test revset support
+
+  $ cat <<'EOF' >> .hg/hgrc
+  > [extdata]
+  > filedata = file:extdata.txt
+  > shelldata = shell:cat extdata.txt | grep 2
+  > EOF
+  $ cat <<'EOF' > extdata.txt
+  > 2
+  > 3
+  > EOF
+
+  $ hg log -qr "extdata(filedata)"
+  2:f6ed99a58333
+  3:9de260b1e88e
+  $ hg log -qr "extdata(shelldata)"
+  2:f6ed99a58333
+
+test weight of extdata() revset
+
+  $ hg debugrevspec -p optimized "extdata(filedata) & 3"
+  * optimized:
+  (andsmally
+    (func
+      (symbol 'extdata')
+      (symbol 'filedata'))
+    (symbol '3'))
+  3
+
+test bad extdata() revset source
+
+  $ hg log -qr "extdata()"
+  hg: parse error: extdata takes at least 1 string argument
+  [255]
+  $ hg log -qr "extdata(unknown)"
+  abort: unknown extdata source 'unknown'
+  [255]
+
+we don't fix up relative file URLs, but we do run shell commands in repo root
+
+  $ mkdir sub
+  $ cd sub
+  $ hg log -qr "extdata(filedata)"
+  abort: error: No such file or directory
+  [255]
+  $ hg log -qr "extdata(shelldata)"
+  2:f6ed99a58333
+
+  $ cd ..