test-revert: add case where file is unchanged between "base" and "parent"

This test highlights a minor misbehavior in the message displayed
during an explicit revert with a target revision.

tests/test-revert.t

@@ -1,671 +1,690 b''
   $ hg init repo
   $ cd repo
   $ echo 123 > a
   $ echo 123 > c
   $ echo 123 > e
   $ hg add a c e
   $ hg commit -m "first" a c e
 
 nothing changed
 
   $ hg revert
   abort: no files or directories specified
   (use --all to revert all files)
   [255]
   $ hg revert --all
 
 Introduce some changes and revert them
 --------------------------------------
 
   $ echo 123 > b
 
   $ hg status
   ? b
   $ echo 12 > c
 
   $ hg status
   M c
   ? b
   $ hg add b
 
   $ hg status
   M c
   A b
   $ hg rm a
 
   $ hg status
   M c
   A b
   R a
 
 revert removal of a file
 
   $ hg revert a
   $ hg status
   M c
   A b
 
 revert addition of a file
 
   $ hg revert b
   $ hg status
   M c
   ? b
 
 revert modification of a file (--no-backup)
 
   $ hg revert --no-backup c
   $ hg status
   ? b
 
 revert deletion (! status) of a added file
 ------------------------------------------
 
   $ hg add b
 
   $ hg status b
   A b
   $ rm b
   $ hg status b
   ! b
   $ hg revert -v b
   forgetting b
   $ hg status b
   b: * (glob)
 
   $ ls
   a
   c
   e
 
 Test creation of backup (.orig) files
 -------------------------------------
 
   $ echo z > e
   $ hg revert --all -v
   saving current version of e as e.orig
   reverting e
 
 revert on clean file (no change)
 --------------------------------
 
   $ hg revert a
   no changes needed to a
 
 revert on an untracked file
 ---------------------------
 
   $ echo q > q
   $ hg revert q
   file not managed: q
   $ rm q
 
 revert on file that does not exists
 -----------------------------------
 
   $ hg revert notfound
   notfound: no such file in rev 334a9e57682c
   $ touch d
   $ hg add d
   $ hg rm a
   $ hg commit -m "second"
   $ echo z > z
   $ hg add z
   $ hg st
   A z
   ? e.orig
 
 revert to another revision (--rev)
 ----------------------------------
 
   $ hg revert --all -r0
   adding a
   removing d
   forgetting z
 
 revert explicitly to parent (--rev)
 -----------------------------------
 
   $ hg revert --all -rtip
   forgetting a
   undeleting d
   $ rm a *.orig
 
 revert to another revision (--rev) and exact match
 --------------------------------------------------
 
 exact match are more silent
 
   $ hg revert -r0 a
   $ hg st a
   A a
   $ hg rm d
   $ hg st d
   R d
 
 should silently keep d removed
 
   $ hg revert -r0 d
   $ hg st d
   R d
 
   $ hg update -C
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved
 
 revert of exec bit
 ------------------
 
 #if execbit
   $ chmod +x c
   $ hg revert --all
   reverting c
 
   $ test -x c || echo non-executable
   non-executable
 
   $ chmod +x c
   $ hg commit -m exe
 
   $ chmod -x c
   $ hg revert --all
   reverting c
 
   $ test -x c && echo executable
   executable
 #endif
 
   $ cd ..
 
 
 Issue241: update and revert produces inconsistent repositories
 --------------------------------------------------------------
 
   $ hg init a
   $ cd a
   $ echo a >> a
   $ hg commit -A -d '1 0' -m a
   adding a
   $ echo a >> a
   $ hg commit -d '2 0' -m a
   $ hg update 0
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ mkdir b
   $ echo b > b/b
 
 call `hg revert` with no file specified
 ---------------------------------------
 
   $ hg revert -rtip
   abort: no files or directories specified
   (use --all to revert all files, or 'hg update 1' to update)
   [255]
 
 call `hg revert` with --all
 ---------------------------
 
   $ hg revert --all -rtip
   reverting a
 
 
 Issue332: confusing message when reverting directory
 ----------------------------------------------------
 
   $ hg ci -A -m b
   adding b/b
   created new head
   $ echo foobar > b/b
   $ mkdir newdir
   $ echo foo > newdir/newfile
   $ hg add newdir/newfile
   $ hg revert b newdir
   reverting b/b (glob)
   forgetting newdir/newfile (glob)
   $ echo foobar > b/b
   $ hg revert .
   reverting b/b (glob)
 
 
 reverting a rename target should revert the source
 --------------------------------------------------
 
   $ hg mv a newa
   $ hg revert newa
   $ hg st a newa
   ? newa
 
   $ cd ..
 
   $ hg init ignored
   $ cd ignored
   $ echo '^ignored$' > .hgignore
   $ echo '^ignoreddir$' >> .hgignore
   $ echo '^removed$' >> .hgignore
 
   $ mkdir ignoreddir
   $ touch ignoreddir/file
   $ touch ignoreddir/removed
   $ touch ignored
   $ touch removed
 
 4 ignored files (we will add/commit everything)
 
   $ hg st -A -X .hgignore
   I ignored
   I ignoreddir/file
   I ignoreddir/removed
   I removed
   $ hg ci -qAm 'add files' ignored ignoreddir/file ignoreddir/removed removed
 
   $ echo >> ignored
   $ echo >> ignoreddir/file
   $ hg rm removed ignoreddir/removed
 
 should revert ignored* and undelete *removed
 --------------------------------------------
 
   $ hg revert -a --no-backup
   reverting ignored
   reverting ignoreddir/file (glob)
   undeleting ignoreddir/removed (glob)
   undeleting removed
   $ hg st -mardi
 
   $ hg up -qC
   $ echo >> ignored
   $ hg rm removed
 
 should silently revert the named files
 --------------------------------------
 
   $ hg revert --no-backup ignored removed
   $ hg st -mardi
 
 Reverting copy (issue3920)
 --------------------------
 
 someone set up us the copies
 
   $ rm .hgignore
   $ hg update -C
   0 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ hg mv ignored allyour
   $ hg copy removed base
   $ hg commit -m rename
 
 copies and renames, you have no chance to survive make your time (issue3920)
 
   $ hg update '.^'
   1 files updated, 0 files merged, 2 files removed, 0 files unresolved
   $ hg revert -rtip -a
   adding allyour
   adding base
   removing ignored
   $ hg status -C
   A allyour
     ignored
   A base
     removed
   R ignored
 
 Test revert of a file added by one side of the merge
 ====================================================
 
 remove any pending change
 
   $ hg revert --all
   forgetting allyour
   forgetting base
   undeleting ignored
   $ hg purge --all --config extensions.purge=
 
 Adds a new commit
 
   $ echo foo > newadd
   $ hg add newadd
   $ hg commit -m 'other adds'
   created new head
 
 
 merge it with the other head
 
   $ hg merge # merge 1 into 2
   2 files updated, 0 files merged, 1 files removed, 0 files unresolved
   (branch merge, don't forget to commit)
   $ hg summary
   parent: 2:b8ec310b2d4e tip
    other adds
   parent: 1:f6180deb8fbe 
    rename
   branch: default
   commit: 2 modified, 1 removed (merge)
   update: (current)
 
 clarifies who added what
 
   $ hg status
   M allyour
   M base
   R ignored
   $ hg status --change 'p1()'
   A newadd
   $ hg status --change 'p2()'
   A allyour
   A base
   R ignored
 
 revert file added by p1() to p1() state
 -----------------------------------------
 
   $ hg revert -r 'p1()' 'glob:newad?'
   $ hg status
   M allyour
   M base
   R ignored
 
 revert file added by p1() to p2() state
 ------------------------------------------
 
   $ hg revert -r 'p2()' 'glob:newad?'
   removing newadd
   $ hg status
   M allyour
   M base
   R ignored
   R newadd
 
 revert file added by p2() to p2() state
 ------------------------------------------
 
   $ hg revert -r 'p2()' 'glob:allyou?'
   $ hg status
   M allyour
   M base
   R ignored
   R newadd
 
 revert file added by p2() to p1() state
 ------------------------------------------
 
   $ hg revert -r 'p1()' 'glob:allyou?'
   removing allyour
   $ hg status
   M base
   R allyour
   R ignored
   R newadd
 
 Systematic behavior validation of most possible cases
 =====================================================
 
 This section tests most of the possible combinations of working directory
 changes and inter-revision changes. The number of possible cases is significant
 but they all have a slighly different handling. So this section commits to
 generating and testing all of them to allow safe refactoring of the revert code.
 
 A python script is used to generate a file history for each combination of
 changes between, on one side the working directory and its parent and on
 the other side, changes between a revert target (--rev) and working directory
 parent. The three states generated are:
 
 - a "base" revision
 - a "parent" revision
 - the working directory (based on "parent")
 
 The file generated have names of the form:
 
  <changeset-state>_<working-copy-state>
 
 Here, "changeset-state" conveys the state in "base" and "parent" (or the change
 that happen between them), "working-copy-state" is self explanatory.
 
 All known states are not tested yet. See inline documentation for details.
 Special cases from merge and rename are not tested by this section.
 
 There are also multiple cases where the current revert implementation is known to
 slightly misbehave.
 
 Write the python script to disk
 -------------------------------
 
   $ cat << EOF > gen-revert-cases.py
   > # generate proper file state to test revert behavior
   > import sys
   > import os
   > 
   > # content of the file in "base" and "parent"
   > # None means no file at all
   > ctxcontent = {
+  >     # clean: no change from base to parent
+  >     'clean': ['base', 'base'],
   >     # modified: file content change from base to parent
   >     'modified': ['base', 'parent'],
   >     # added: file is missing from base and added in parent
   >     'added': [None, 'parent'],
   > }
   > 
   > # content of file in working copy
   > wccontent = {
   >     # clean: wc content is the same as parent
   >     'clean': lambda cc: cc[1],
   > }
   > 
   > # build the combination of possible states
   > combination = []
   > for ctxkey in ctxcontent:
   >     for wckey in wccontent:
   >         filename = "%s_%s" % (ctxkey, wckey)
   >         combination.append((filename, ctxkey, wckey))
   > 
   > # make sure we have stable output
   > combination.sort()
   > 
   > # retrieve the state we must generate
   > target = sys.argv[1]
   > 
   > # compute file content
   > content = []
   > for filename, ctxkey, wckey in combination:
   >     cc = ctxcontent[ctxkey]
   >     if target == 'filelist':
   >         print filename
   >     elif target == 'base':
   >         content.append((filename, cc[0]))
   >     elif target == 'parent':
   >         content.append((filename, cc[1]))
   >     elif target == 'wc':
   >         content.append((filename, wccontent[wckey](cc)))
   >     else:
   >         print >> sys.stderr, "unknown target:", target
   >         sys.exit(1)
   > 
   > # write actual content
   > for filename, data in content:
   >     if data is not None:
   >         f = open(filename, 'w')
   >         f.write(data + '\n')
   >         f.close()
   >     elif os.path.exists(filename):
   >        os.remove(filename)
   > EOF
 
 check list of planned files
 
   $ python gen-revert-cases.py filelist
   added_clean
+  clean_clean
   modified_clean
 
 Script to make a simple text version of the content
 ---------------------------------------------------
 
   $ cat << EOF >> dircontent.py
   > # generate a simple text view of the directory for easy comparison
   > import os
   > files = os.listdir('.')
   > files.sort()
   > for filename in files:
   >     if os.path.isdir(filename):
   >         continue
   >     content = open(filename).read()
   >     print '%-6s %s' % (content.strip(), filename)
   > EOF
 
 Generate appropriate repo state
 -------------------------------
 
   $ hg init revert-ref
   $ cd revert-ref
 
 Generate base changeset
 
   $ python ../gen-revert-cases.py base
   $ hg addremove --similarity 0
+  adding clean_clean
   adding modified_clean
   $ hg status
+  A clean_clean
   A modified_clean
   $ hg commit -m 'base'
 
 (create a simple text version of the content)
 
   $ python ../dircontent.py > ../content-base.txt
   $ cat ../content-base.txt
+  base   clean_clean
   base   modified_clean
 
 Create parent changeset
 
   $ python ../gen-revert-cases.py parent
   $ hg addremove --similarity 0
   adding added_clean
   $ hg status
   M modified_clean
   A added_clean
   $ hg commit -m 'parent'
 
 (create a simple text version of the content)
 
   $ python ../dircontent.py > ../content-parent.txt
   $ cat ../content-parent.txt
   parent added_clean
+  base   clean_clean
   parent modified_clean
 
 Setup working directory
 
   $ python ../gen-revert-cases.py wc | cat
   $ hg addremove --similarity 0
   $ hg status
 
   $ hg status --rev 'desc("base")'
   M modified_clean
   A added_clean
 
 (create a simple text version of the content)
 
   $ python ../dircontent.py > ../content-wc.txt
   $ cat ../content-wc.txt
   parent added_clean
+  base   clean_clean
   parent modified_clean
 
   $ cd ..
 
 Test revert --all to parent content
 -----------------------------------
 
 (setup from reference repo)
 
   $ cp -r revert-ref revert-parent-all
   $ cd revert-parent-all
 
 check revert output
 
   $ hg revert --all
 
 Compare resulting directory with revert target.
 
 The diff is filtered to include change only. The only difference should be
 additional `.orig` backup file when applicable.
 
   $ python ../dircontent.py > ../content-parent-all.txt
   $ cd ..
   $ diff -U 0 -- content-parent.txt content-parent-all.txt | grep _
   [1]
 
 Test revert --all to "base" content
 -----------------------------------
 
 (setup from reference repo)
 
   $ cp -r revert-ref revert-base-all
   $ cd revert-base-all
 
 check revert output
 
   $ hg revert --all --rev 'desc(base)'
   removing added_clean
   reverting modified_clean
 
 Compare resulting directory with revert target.
 
 The diff is filtered to include change only. The only difference should be
 additional `.orig` backup file when applicable.
 
   $ python ../dircontent.py > ../content-base-all.txt
   $ cd ..
   $ diff -U 0 -- content-base.txt content-base-all.txt | grep _
   [1]
 
 Test revert to parent content with explicit file name
 -----------------------------------------------------
 
 (setup from reference repo)
 
   $ cp -r revert-ref revert-parent-explicit
   $ cd revert-parent-explicit
 
 revert all files individually and check the output
 (output is expected to be different than in the --all case)
 
   $ for file in `python ../gen-revert-cases.py filelist`; do
   >   echo '### revert for:' $file;
   >   hg revert $file;
   >   echo
   > done
   ### revert for: added_clean
   no changes needed to added_clean
   
+  ### revert for: clean_clean
+  no changes needed to clean_clean
+  
   ### revert for: modified_clean
   no changes needed to modified_clean
   
 
 check resulting directory againt the --all run
 (There should be no difference)
 
   $ python ../dircontent.py > ../content-parent-explicit.txt
   $ cd ..
   $ diff -U 0 -- content-parent-all.txt content-parent-explicit.txt | grep _
   [1]
 
 Test revert to "base" content with explicit file name
 -----------------------------------------------------
 
 (setup from reference repo)
 
   $ cp -r revert-ref revert-base-explicit
   $ cd revert-base-explicit
 
 revert all files individually and check the output
 (output is expected to be different than in the --all case)
 
+Misbehavior:
+
+- fails to report no change to revert for
+|
+| - clean_clean
+
   $ for file in `python ../gen-revert-cases.py filelist`; do
   >   echo '### revert for:' $file;
   >   hg revert $file --rev 'desc(base)';
   >   echo
   > done
   ### revert for: added_clean
   
+  ### revert for: clean_clean
+  
   ### revert for: modified_clean
   
 
 check resulting directory againt the --all run
 (There should be no difference)
 
   $ python ../dircontent.py > ../content-base-explicit.txt
   $ cd ..
   $ diff -U 0 -- content-base-all.txt content-base-explicit.txt | grep _
   [1]