tests: conditionalize tests based on presence of custom extensions

tests: conditionalize tests based on presence of custom extensions

The test harness supports injecting extensions via --extra-config-opt.
However, if you do this, various tests that print state about loaded
extensions fail.

This commit teaches the test harness to recognize when custom
extensions are loaded so that tests can use feature sniffing to
conditionalize tests based on that.

Differential Revision: https://phab.mercurial-scm.org/D3039

--- a/tests/helpers-testrepo.sh	Wed Apr 04 12:16:50 2018 -0700
+++ b/tests/helpers-testrepo.sh	Wed Apr 04 13:21:34 2018 -0700
@@ -9,6 +9,13 @@
 # The mercurial source repository was typically orignally cloned with the
 # system mercurial installation, and may require extensions or settings from
 # the system installation.
+
+if [ -n $HGTESTEXTRAEXTENSIONS ]; then
+    for extension in $HGTESTEXTRAEXTENSIONS; do
+        extraoptions="$extraoptions --config extensions.$extension=!"
+    done
+fi
+
 syshg () {
     (
         syshgenv
@@ -48,6 +55,6 @@
     alias testrepohg=syshg
     alias testrepohgenv=syshgenv
 else
-    alias testrepohg=hg
+    alias testrepohg="hg $extraoptions"
     alias testrepohgenv=:
 fi

--- a/tests/hghave.py	Wed Apr 04 12:16:50 2018 -0700
+++ b/tests/hghave.py	Wed Apr 04 13:21:34 2018 -0700
@@ -718,6 +718,10 @@
     except (ImportError, AttributeError):
         return False
 
+@check('extraextensions', 'whether tests are running with extra extensions')
+def has_extraextensions():
+    return 'HGTESTEXTRAEXTENSIONS' in os.environ
+
 def getrepofeatures():
     """Obtain set of repository features in use.
 

--- a/tests/run-tests.py	Wed Apr 04 12:16:50 2018 -0700
+++ b/tests/run-tests.py	Wed Apr 04 13:21:34 2018 -0700
@@ -1070,6 +1070,17 @@
         env["HGENCODINGMODE"] = "strict"
         env['HGIPV6'] = str(int(self._useipv6))
 
+        extraextensions = []
+        for opt in self._extraconfigopts:
+            section, key = opt.encode('utf-8').split(b'.', 1)
+            if section != 'extensions':
+                continue
+            name = key.split(b'=', 1)[0]
+            extraextensions.append(name)
+
+        if extraextensions:
+            env['HGTESTEXTRAEXTENSIONS'] = b' '.join(extraextensions)
+
         # LOCALIP could be ::1 or 127.0.0.1. Useful for tests that require raw
         # IP addresses.
         env['LOCALIP'] = self._localip()

--- a/tests/test-basic.t	Wed Apr 04 12:16:50 2018 -0700
+++ b/tests/test-basic.t	Wed Apr 04 13:21:34 2018 -0700
@@ -1,5 +1,6 @@
 Create a repository:
 
+#if no-extraextensions
   $ hg config
   devel.all-warnings=true
   devel.default-date=0 0
@@ -13,6 +14,8 @@
   web.address=localhost
   web\.ipv6=(?:True|False) (re)
   web.server-header=testing stub value
+#endif
+
   $ hg init t
   $ cd t
 

--- a/tests/test-debugextensions.t	Wed Apr 04 12:16:50 2018 -0700
+++ b/tests/test-debugextensions.t	Wed Apr 04 13:21:34 2018 -0700
@@ -1,4 +1,6 @@
+#if no-extraextensions
   $ hg debugextensions
+#endif
 
   $ debugpath=`pwd`/extwithoutinfos.py
 
@@ -19,6 +21,10 @@
   > ext2 = `pwd`/extwithinfos.py
   > EOF
 
+  $ for extension in $HGTESTEXTRAEXTENSIONS; do
+  >     echo "$extension=!" >> $HGRCPATH
+  > done
+
   $ hg debugextensions
   ext1 (untested!)
   ext2 (3.2.1!)

--- a/tests/test-extension.t	Wed Apr 04 12:16:50 2018 -0700
+++ b/tests/test-extension.t	Wed Apr 04 13:21:34 2018 -0700
@@ -867,9 +867,11 @@
 Show extensions:
 (note that mq force load strip, also checking it's not loaded twice)
 
+#if no-extraextensions
   $ hg debugextensions
   mq
   strip
+#endif
 
 For extensions, which name matches one of its commands, help
 message should ask '-v -e' to get list of built-in aliases

--- a/tests/test-globalopts.t	Wed Apr 04 12:16:50 2018 -0700
+++ b/tests/test-globalopts.t	Wed Apr 04 13:21:34 2018 -0700
@@ -289,6 +289,8 @@
 
 Testing -h/--help:
 
+#if no-extraextensions
+
   $ hg -h
   Mercurial Distributed SCM
   
@@ -372,8 +374,6 @@
   
   (use 'hg help -v' to show built-in aliases and global options)
 
-
-
   $ hg --help
   Mercurial Distributed SCM
   
@@ -457,5 +457,7 @@
   
   (use 'hg help -v' to show built-in aliases and global options)
 
+#endif
+
 Not tested: --debugger
 

--- a/tests/test-help.t	Wed Apr 04 12:16:50 2018 -0700
+++ b/tests/test-help.t	Wed Apr 04 13:21:34 2018 -0700
@@ -44,6 +44,10 @@
    summary       summarize working directory state
    update        update working directory (or switch revisions)
 
+Extra extensions will be printed in help output in a non-reliable order since
+the extension is unknown.
+#if no-extraextensions
+
   $ hg help
   Mercurial Distributed SCM
   
@@ -283,6 +287,8 @@
        win32mbcs     allow the use of MBCS paths with problematic encodings
        zeroconf      discover and advertise repositories on the local network
 
+#endif
+
 Verify that deprecated extensions are included if --verbose:
 
   $ hg -v help extensions | grep children
@@ -816,6 +822,8 @@
 
 Test that default list of commands omits extension commands
 
+#if no-extraextensions
+
   $ hg help
   Mercurial Distributed SCM
   
@@ -903,6 +911,7 @@
   
   (use 'hg help -v' to show built-in aliases and global options)
 
+#endif
 
 Test list of internal help commands