Mercurial > hg-stable
view tests/test-fix.t @ 38127:e504fa630860
tests: use [(] instead of \( to avoid warning on py3
From a recent test run of mine:
run-tests.py:1633: DeprecationWarning: invalid escape sequence '\('
This lets us encode the expectation without the badness.
Differential Revision: https://phab.mercurial-scm.org/D3621
author | Augie Fackler <augie@google.com> |
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date | Sat, 19 May 2018 15:47:32 -0400 |
parents | 80695628adcb |
children | f068495a1c28 |
line wrap: on
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A script that implements uppercasing of specific lines in a file. This approximates the behavior of code formatters well enough for our tests. $ UPPERCASEPY="$TESTTMP/uppercase.py" $ cat > $UPPERCASEPY <<EOF > import sys > from mercurial.utils.procutil import setbinary > setbinary(sys.stdin) > setbinary(sys.stdout) > lines = set() > for arg in sys.argv[1:]: > if arg == 'all': > sys.stdout.write(sys.stdin.read().upper()) > sys.exit(0) > else: > first, last = arg.split('-') > lines.update(range(int(first), int(last) + 1)) > for i, line in enumerate(sys.stdin.readlines()): > if i + 1 in lines: > sys.stdout.write(line.upper()) > else: > sys.stdout.write(line) > EOF $ TESTLINES="foo\nbar\nbaz\nqux\n" $ printf $TESTLINES | $PYTHON $UPPERCASEPY foo bar baz qux $ printf $TESTLINES | $PYTHON $UPPERCASEPY all FOO BAR BAZ QUX $ printf $TESTLINES | $PYTHON $UPPERCASEPY 1-1 FOO bar baz qux $ printf $TESTLINES | $PYTHON $UPPERCASEPY 1-2 FOO BAR baz qux $ printf $TESTLINES | $PYTHON $UPPERCASEPY 2-3 foo BAR BAZ qux $ printf $TESTLINES | $PYTHON $UPPERCASEPY 2-2 4-4 foo BAR baz QUX Set up the config with two simple fixers: one that fixes specific line ranges, and one that always fixes the whole file. They both "fix" files by converting letters to uppercase. They use different file extensions, so each test case can choose which behavior to use by naming files. $ cat >> $HGRCPATH <<EOF > [extensions] > fix = > [experimental] > evolution.createmarkers=True > evolution.allowunstable=True > [fix] > uppercase-whole-file:command=$PYTHON $UPPERCASEPY all > uppercase-whole-file:fileset=set:**.whole > uppercase-changed-lines:command=$PYTHON $UPPERCASEPY > uppercase-changed-lines:linerange={first}-{last} > uppercase-changed-lines:fileset=set:**.changed > EOF Help text for fix. $ hg help fix hg fix [OPTION]... [FILE]... rewrite file content in changesets or working directory Runs any configured tools to fix the content of files. Only affects files with changes, unless file arguments are provided. Only affects changed lines of files, unless the --whole flag is used. Some tools may always affect the whole file regardless of --whole. If revisions are specified with --rev, those revisions will be checked, and they may be replaced with new revisions that have fixed file content. It is desirable to specify all descendants of each specified revision, so that the fixes propagate to the descendants. If all descendants are fixed at the same time, no merging, rebasing, or evolution will be required. If --working-dir is used, files with uncommitted changes in the working copy will be fixed. If the checked-out revision is also fixed, the working directory will update to the replacement revision. When determining what lines of each file to fix at each revision, the whole set of revisions being fixed is considered, so that fixes to earlier revisions are not forgotten in later ones. The --base flag can be used to override this default behavior, though it is not usually desirable to do so. (use 'hg help -e fix' to show help for the fix extension) options ([+] can be repeated): --all fix all non-public non-obsolete revisions --base REV [+] revisions to diff against (overrides automatic selection, and applies to every revision being fixed) -r --rev REV [+] revisions to fix -w --working-dir fix the working directory --whole always fix every line of a file (some details hidden, use --verbose to show complete help) $ hg help -e fix fix extension - rewrite file content in changesets or working copy (EXPERIMENTAL) Provides a command that runs configured tools on the contents of modified files, writing back any fixes to the working copy or replacing changesets. Here is an example configuration that causes 'hg fix' to apply automatic formatting fixes to modified lines in C++ code: [fix] clang-format:command=clang-format --assume-filename={rootpath} clang-format:linerange=--lines={first}:{last} clang-format:fileset=set:**.cpp or **.hpp The :command suboption forms the first part of the shell command that will be used to fix a file. The content of the file is passed on standard input, and the fixed file content is expected on standard output. If there is any output on standard error, the file will not be affected. Some values may be substituted into the command: {rootpath} The path of the file being fixed, relative to the repo root {basename} The name of the file being fixed, without the directory path If the :linerange suboption is set, the tool will only be run if there are changed lines in a file. The value of this suboption is appended to the shell command once for every range of changed lines in the file. Some values may be substituted into the command: {first} The 1-based line number of the first line in the modified range {last} The 1-based line number of the last line in the modified range The :fileset suboption determines which files will be passed through each configured tool. See 'hg help fileset' for possible values. If there are file arguments to 'hg fix', the intersection of these filesets is used. There is also a configurable limit for the maximum size of file that will be processed by 'hg fix': [fix] maxfilesize=2MB list of commands: fix rewrite file content in changesets or working directory (use 'hg help -v -e fix' to show built-in aliases and global options) There is no default behavior in the absence of --rev and --working-dir. $ hg init badusage $ cd badusage $ hg fix abort: no changesets specified (use --rev or --working-dir) [255] $ hg fix --whole abort: no changesets specified (use --rev or --working-dir) [255] $ hg fix --base 0 abort: no changesets specified (use --rev or --working-dir) [255] Fixing a public revision isn't allowed. It should abort early enough that nothing happens, even to the working directory. $ printf "hello\n" > hello.whole $ hg commit -Aqm "hello" $ hg phase -r 0 --public $ hg fix -r 0 abort: can't fix immutable changeset 0:6470986d2e7b [255] $ hg fix -r 0 --working-dir abort: can't fix immutable changeset 0:6470986d2e7b [255] $ hg cat -r tip hello.whole hello $ cat hello.whole hello $ cd .. Fixing a clean working directory should do nothing. Even the --whole flag shouldn't cause any clean files to be fixed. Specifying a clean file explicitly should only fix it if the fixer always fixes the whole file. The combination of an explicit filename and --whole should format the entire file regardless. $ hg init fixcleanwdir $ cd fixcleanwdir $ printf "hello\n" > hello.changed $ printf "world\n" > hello.whole $ hg commit -Aqm "foo" $ hg fix --working-dir $ hg diff $ hg fix --working-dir --whole $ hg diff $ hg fix --working-dir * $ cat * hello WORLD $ hg revert --all --no-backup reverting hello.whole $ hg fix --working-dir * --whole $ cat * HELLO WORLD The same ideas apply to fixing a revision, so we create a revision that doesn't modify either of the files in question and try fixing it. This also tests that we ignore a file that doesn't match any configured fixer. $ hg revert --all --no-backup reverting hello.changed reverting hello.whole $ printf "unimportant\n" > some.file $ hg commit -Aqm "some other file" $ hg fix -r . $ hg cat -r tip * hello world unimportant $ hg fix -r . --whole $ hg cat -r tip * hello world unimportant $ hg fix -r . * $ hg cat -r tip * hello WORLD unimportant $ hg fix -r . * --whole --config experimental.evolution.allowdivergence=true 2 new content-divergent changesets $ hg cat -r tip * HELLO WORLD unimportant $ cd .. Fixing the working directory should still work if there are no revisions. $ hg init norevisions $ cd norevisions $ printf "something\n" > something.whole $ hg add adding something.whole $ hg fix --working-dir $ cat something.whole SOMETHING $ cd .. Test the effect of fixing the working directory for each possible status, with and without providing explicit file arguments. $ hg init implicitlyfixstatus $ cd implicitlyfixstatus $ printf "modified\n" > modified.whole $ printf "removed\n" > removed.whole $ printf "deleted\n" > deleted.whole $ printf "clean\n" > clean.whole $ printf "ignored.whole" > .hgignore $ hg commit -Aqm "stuff" $ printf "modified!!!\n" > modified.whole $ printf "unknown\n" > unknown.whole $ printf "ignored\n" > ignored.whole $ printf "added\n" > added.whole $ hg add added.whole $ hg remove removed.whole $ rm deleted.whole $ hg status --all M modified.whole A added.whole R removed.whole ! deleted.whole ? unknown.whole I ignored.whole C .hgignore C clean.whole $ hg fix --working-dir $ hg status --all M modified.whole A added.whole R removed.whole ! deleted.whole ? unknown.whole I ignored.whole C .hgignore C clean.whole $ cat *.whole ADDED clean ignored MODIFIED!!! unknown $ printf "modified!!!\n" > modified.whole $ printf "added\n" > added.whole $ hg fix --working-dir *.whole $ hg status --all M clean.whole M modified.whole A added.whole R removed.whole ! deleted.whole ? unknown.whole I ignored.whole C .hgignore It would be better if this also fixed the unknown file. $ cat *.whole ADDED CLEAN ignored MODIFIED!!! unknown $ cd .. Test that incremental fixing works on files with additions, deletions, and changes in multiple line ranges. Note that deletions do not generally cause neighboring lines to be fixed, so we don't return a line range for purely deleted sections. In the future we should support a :deletion config that allows fixers to know where deletions are located. $ hg init incrementalfixedlines $ cd incrementalfixedlines $ printf "a\nb\nc\nd\ne\nf\ng\n" > foo.txt $ hg commit -Aqm "foo" $ printf "zz\na\nc\ndd\nee\nff\nf\ngg\n" > foo.txt $ hg --config "fix.fail:command=echo" \ > --config "fix.fail:linerange={first}:{last}" \ > --config "fix.fail:fileset=foo.txt" \ > fix --working-dir $ cat foo.txt 1:1 4:6 8:8 $ cd .. Test that --whole fixes all lines regardless of the diffs present. $ hg init wholeignoresdiffs $ cd wholeignoresdiffs $ printf "a\nb\nc\nd\ne\nf\ng\n" > foo.changed $ hg commit -Aqm "foo" $ printf "zz\na\nc\ndd\nee\nff\nf\ngg\n" > foo.changed $ hg fix --working-dir --whole $ cat foo.changed ZZ A C DD EE FF F GG $ cd .. We should do nothing with symlinks, and their targets should be unaffected. Any other behavior would be more complicated to implement and harder to document. #if symlink $ hg init dontmesswithsymlinks $ cd dontmesswithsymlinks $ printf "hello\n" > hello.whole $ ln -s hello.whole hellolink $ hg add adding hello.whole adding hellolink $ hg fix --working-dir hellolink $ hg status A hello.whole A hellolink $ cd .. #endif We should allow fixers to run on binary files, even though this doesn't sound like a common use case. There's not much benefit to disallowing it, and users can add "and not binary()" to their filesets if needed. The Mercurial philosophy is generally to not handle binary files specially anyway. $ hg init cantouchbinaryfiles $ cd cantouchbinaryfiles $ printf "hello\0\n" > hello.whole $ hg add adding hello.whole $ hg fix --working-dir 'set:binary()' $ cat hello.whole HELLO\x00 (esc) $ cd .. We have a config for the maximum size of file we will attempt to fix. This can be helpful to avoid running unsuspecting fixer tools on huge inputs, which could happen by accident without a well considered configuration. A more precise configuration could use the size() fileset function if one global limit is undesired. $ hg init maxfilesize $ cd maxfilesize $ printf "this file is huge\n" > hello.whole $ hg add adding hello.whole $ hg --config fix.maxfilesize=10 fix --working-dir ignoring file larger than 10 bytes: hello.whole $ cat hello.whole this file is huge $ cd .. If we specify a file to fix, other files should be left alone, even if they have changes. $ hg init fixonlywhatitellyouto $ cd fixonlywhatitellyouto $ printf "fix me!\n" > fixme.whole $ printf "not me.\n" > notme.whole $ hg add adding fixme.whole adding notme.whole $ hg fix --working-dir fixme.whole $ cat *.whole FIX ME! not me. $ cd .. Specifying a directory name should fix all its files and subdirectories. $ hg init fixdirectory $ cd fixdirectory $ mkdir -p dir1/dir2 $ printf "foo\n" > foo.whole $ printf "bar\n" > dir1/bar.whole $ printf "baz\n" > dir1/dir2/baz.whole $ hg add adding dir1/bar.whole adding dir1/dir2/baz.whole adding foo.whole $ hg fix --working-dir dir1 $ cat foo.whole dir1/bar.whole dir1/dir2/baz.whole foo BAR BAZ $ cd .. Fixing a file in the working directory that needs no fixes should not actually write back to the file, so for example the mtime shouldn't change. $ hg init donttouchunfixedfiles $ cd donttouchunfixedfiles $ printf "NO FIX NEEDED\n" > foo.whole $ hg add adding foo.whole $ cp -p foo.whole foo.whole.orig $ cp -p foo.whole.orig foo.whole $ sleep 2 # mtime has a resolution of one or two seconds. $ hg fix --working-dir $ f foo.whole.orig --newer foo.whole foo.whole.orig: newer than foo.whole $ cd .. When a fixer prints to stderr, we assume that it has failed. We should show the error messages to the user, and we should not let the failing fixer affect the file it was fixing (many code formatters might emit error messages on stderr and nothing on stdout, which would cause us the clear the file). We show the user which fixer failed and which revision, but we assume that the fixer will print the filename if it is relevant. $ hg init showstderr $ cd showstderr $ printf "hello\n" > hello.txt $ hg add adding hello.txt $ cat >> $TESTTMP/cmd.sh <<'EOF' > printf 'HELLO\n' > printf "$@: some\nerror" >&2 > EOF $ hg --config "fix.fail:command=sh $TESTTMP/cmd.sh {rootpath}" \ > --config "fix.fail:fileset=hello.txt" \ > fix --working-dir [wdir] fail: hello.txt: some [wdir] fail: error $ cat hello.txt hello $ cd .. Fixing the working directory and its parent revision at the same time should check out the replacement revision for the parent. This prevents any new uncommitted changes from appearing. We test this for a clean working directory and a dirty one. In both cases, all lines/files changed since the grandparent will be fixed. The grandparent is the "baserev" for both the parent and the working copy. $ hg init fixdotandcleanwdir $ cd fixdotandcleanwdir $ printf "hello\n" > hello.whole $ printf "world\n" > world.whole $ hg commit -Aqm "the parent commit" $ hg parents --template '{rev} {desc}\n' 0 the parent commit $ hg fix --working-dir -r . $ hg parents --template '{rev} {desc}\n' 1 the parent commit $ hg cat -r . *.whole HELLO WORLD $ cat *.whole HELLO WORLD $ hg status $ cd .. Same test with a dirty working copy. $ hg init fixdotanddirtywdir $ cd fixdotanddirtywdir $ printf "hello\n" > hello.whole $ printf "world\n" > world.whole $ hg commit -Aqm "the parent commit" $ printf "hello,\n" > hello.whole $ printf "world!\n" > world.whole $ hg parents --template '{rev} {desc}\n' 0 the parent commit $ hg fix --working-dir -r . $ hg parents --template '{rev} {desc}\n' 1 the parent commit $ hg cat -r . *.whole HELLO WORLD $ cat *.whole HELLO, WORLD! $ hg status M hello.whole M world.whole $ cd .. When we have a chain of commits that change mutually exclusive lines of code, we should be able to do incremental fixing that causes each commit in the chain to include fixes made to the previous commits. This prevents children from backing out the fixes made in their parents. A dirty working directory is conceptually similar to another commit in the chain. $ hg init incrementallyfixchain $ cd incrementallyfixchain $ cat > file.changed <<EOF > first > second > third > fourth > fifth > EOF $ hg commit -Aqm "the common ancestor (the baserev)" $ cat > file.changed <<EOF > first (changed) > second > third > fourth > fifth > EOF $ hg commit -Aqm "the first commit to fix" $ cat > file.changed <<EOF > first (changed) > second > third (changed) > fourth > fifth > EOF $ hg commit -Aqm "the second commit to fix" $ cat > file.changed <<EOF > first (changed) > second > third (changed) > fourth > fifth (changed) > EOF $ hg fix -r . -r '.^' --working-dir $ hg parents --template '{rev}\n' 4 $ hg cat -r '.^^' file.changed first second third fourth fifth $ hg cat -r '.^' file.changed FIRST (CHANGED) second third fourth fifth $ hg cat -r . file.changed FIRST (CHANGED) second THIRD (CHANGED) fourth fifth $ cat file.changed FIRST (CHANGED) second THIRD (CHANGED) fourth FIFTH (CHANGED) $ cd .. If we incrementally fix a merge commit, we should fix any lines that changed versus either parent. You could imagine only fixing the intersection or some other subset, but this is necessary if either parent is being fixed. It prevents us from forgetting fixes made in either parent. $ hg init incrementallyfixmergecommit $ cd incrementallyfixmergecommit $ printf "a\nb\nc\n" > file.changed $ hg commit -Aqm "ancestor" $ printf "aa\nb\nc\n" > file.changed $ hg commit -m "change a" $ hg checkout '.^' 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ printf "a\nb\ncc\n" > file.changed $ hg commit -m "change c" created new head $ hg merge merging file.changed 0 files updated, 1 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ hg commit -m "merge" $ hg cat -r . file.changed aa b cc $ hg fix -r . --working-dir $ hg cat -r . file.changed AA b CC $ cd .. Abort fixing revisions if there is an unfinished operation. We don't want to make things worse by editing files or stripping/obsoleting things. Also abort fixing the working directory if there are unresolved merge conflicts. $ hg init abortunresolved $ cd abortunresolved $ echo "foo1" > foo.whole $ hg commit -Aqm "foo 1" $ hg update null 0 files updated, 0 files merged, 1 files removed, 0 files unresolved $ echo "foo2" > foo.whole $ hg commit -Aqm "foo 2" $ hg --config extensions.rebase= rebase -r 1 -d 0 rebasing 1:c3b6dc0e177a "foo 2" (tip) merging foo.whole warning: conflicts while merging foo.whole! (edit, then use 'hg resolve --mark') unresolved conflicts (see hg resolve, then hg rebase --continue) [1] $ hg --config extensions.rebase= fix --working-dir abort: unresolved conflicts (use 'hg resolve') [255] $ hg --config extensions.rebase= fix -r . abort: rebase in progress (use 'hg rebase --continue' or 'hg rebase --abort') [255] When fixing a file that was renamed, we should diff against the source of the rename for incremental fixing and we should correctly reproduce the rename in the replacement revision. $ hg init fixrenamecommit $ cd fixrenamecommit $ printf "a\nb\nc\n" > source.changed $ hg commit -Aqm "source revision" $ hg move source.changed dest.changed $ printf "a\nb\ncc\n" > dest.changed $ hg commit -m "dest revision" $ hg fix -r . $ hg log -r tip --copies --template "{file_copies}\n" dest.changed (source.changed) $ hg cat -r tip dest.changed a b CC $ cd .. When fixing revisions that remove files we must ensure that the replacement actually removes the file, whereas it could accidentally leave it unchanged or write an empty string to it. $ hg init fixremovedfile $ cd fixremovedfile $ printf "foo\n" > foo.whole $ printf "bar\n" > bar.whole $ hg commit -Aqm "add files" $ hg remove bar.whole $ hg commit -m "remove file" $ hg status --change . R bar.whole $ hg fix -r . foo.whole $ hg status --change tip M foo.whole R bar.whole $ cd .. If fixing a revision finds no fixes to make, no replacement revision should be created. $ hg init nofixesneeded $ cd nofixesneeded $ printf "FOO\n" > foo.whole $ hg commit -Aqm "add file" $ hg log --template '{rev}\n' 0 $ hg fix -r . $ hg log --template '{rev}\n' 0 $ cd .. If fixing a commit reverts all the changes in the commit, we replace it with a commit that changes no files. $ hg init nochangesleft $ cd nochangesleft $ printf "FOO\n" > foo.whole $ hg commit -Aqm "add file" $ printf "foo\n" > foo.whole $ hg commit -m "edit file" $ hg status --change . M foo.whole $ hg fix -r . $ hg status --change tip $ cd .. If we fix a parent and child revision together, the child revision must be replaced if the parent is replaced, even if the diffs of the child needed no fixes. However, we're free to not replace revisions that need no fixes and have no ancestors that are replaced. $ hg init mustreplacechild $ cd mustreplacechild $ printf "FOO\n" > foo.whole $ hg commit -Aqm "add foo" $ printf "foo\n" > foo.whole $ hg commit -m "edit foo" $ printf "BAR\n" > bar.whole $ hg commit -Aqm "add bar" $ hg log --graph --template '{node|shortest} {files}' @ bc05 bar.whole | o 4fd2 foo.whole | o f9ac foo.whole $ hg fix -r 0:2 $ hg log --graph --template '{node|shortest} {files}' o 3801 bar.whole | o 38cc | | @ bc05 bar.whole | | | x 4fd2 foo.whole |/ o f9ac foo.whole $ cd .. It's also possible that the child needs absolutely no changes, but we still need to replace it to update its parent. If we skipped replacing the child because it had no file content changes, it would become an orphan for no good reason. $ hg init mustreplacechildevenifnop $ cd mustreplacechildevenifnop $ printf "Foo\n" > foo.whole $ hg commit -Aqm "add a bad foo" $ printf "FOO\n" > foo.whole $ hg commit -m "add a good foo" $ hg fix -r . -r '.^' $ hg log --graph --template '{rev} {desc}' o 3 add a good foo | o 2 add a bad foo @ 1 add a good foo | x 0 add a bad foo $ cd .. Similar to the case above, the child revision may become empty as a result of fixing its parent. We should still create an empty replacement child. TODO: determine how this should interact with ui.allowemptycommit given that the empty replacement could have children. $ hg init mustreplacechildevenifempty $ cd mustreplacechildevenifempty $ printf "foo\n" > foo.whole $ hg commit -Aqm "add foo" $ printf "Foo\n" > foo.whole $ hg commit -m "edit foo" $ hg fix -r . -r '.^' $ hg log --graph --template '{rev} {desc}\n' --stat o 3 edit foo | o 2 add foo foo.whole | 1 + 1 files changed, 1 insertions(+), 0 deletions(-) @ 1 edit foo | foo.whole | 2 +- | 1 files changed, 1 insertions(+), 1 deletions(-) | x 0 add foo foo.whole | 1 + 1 files changed, 1 insertions(+), 0 deletions(-) $ cd .. Fixing a secret commit should replace it with another secret commit. $ hg init fixsecretcommit $ cd fixsecretcommit $ printf "foo\n" > foo.whole $ hg commit -Aqm "add foo" --secret $ hg fix -r . $ hg log --template '{rev} {phase}\n' 1 secret 0 secret $ cd .. We should also preserve phase when fixing a draft commit while the user has their default set to secret. $ hg init respectphasesnewcommit $ cd respectphasesnewcommit $ printf "foo\n" > foo.whole $ hg commit -Aqm "add foo" $ hg --config phases.newcommit=secret fix -r . $ hg log --template '{rev} {phase}\n' 1 draft 0 draft $ cd .. Debug output should show what fixer commands are being subprocessed, which is useful for anyone trying to set up a new config. $ hg init debugoutput $ cd debugoutput $ printf "foo\nbar\nbaz\n" > foo.changed $ hg commit -Aqm "foo" $ printf "Foo\nbar\nBaz\n" > foo.changed $ hg --debug fix --working-dir subprocess: * $TESTTMP/uppercase.py 1-1 3-3 (glob) $ cd .. Fixing an obsolete revision can cause divergence, so we abort unless the user configures to allow it. This is not yet smart enough to know whether there is a successor, but even then it is not likely intentional or idiomatic to fix an obsolete revision. $ hg init abortobsoleterev $ cd abortobsoleterev $ printf "foo\n" > foo.changed $ hg commit -Aqm "foo" $ hg debugobsolete `hg parents --template '{node}'` obsoleted 1 changesets $ hg --hidden fix -r 0 abort: fixing obsolete revision could cause divergence [255] $ hg --hidden fix -r 0 --config experimental.evolution.allowdivergence=true $ hg cat -r tip foo.changed FOO $ cd .. Test all of the available substitution values for fixer commands. $ hg init substitution $ cd substitution $ mkdir foo $ printf "hello\ngoodbye\n" > foo/bar $ hg add adding foo/bar $ hg --config "fix.fail:command=printf '%s\n' '{rootpath}' '{basename}'" \ > --config "fix.fail:linerange='{first}' '{last}'" \ > --config "fix.fail:fileset=foo/bar" \ > fix --working-dir $ cat foo/bar foo/bar bar 1 2 $ cd .. The --base flag should allow picking the revisions to diff against for changed files and incremental line formatting. $ hg init baseflag $ cd baseflag $ printf "one\ntwo\n" > foo.changed $ printf "bar\n" > bar.changed $ hg commit -Aqm "first" $ printf "one\nTwo\n" > foo.changed $ hg commit -m "second" $ hg fix -w --base . $ hg status $ hg fix -w --base null $ cat foo.changed ONE TWO $ cat bar.changed BAR $ cd .. If the user asks to fix the parent of another commit, they are asking to create an orphan. We must respect experimental.evolution.allowunstable. $ hg init allowunstable $ cd allowunstable $ printf "one\n" > foo.whole $ hg commit -Aqm "first" $ printf "two\n" > foo.whole $ hg commit -m "second" $ hg --config experimental.evolution.allowunstable=False fix -r '.^' abort: can only fix a changeset together with all its descendants [255] $ hg fix -r '.^' 1 new orphan changesets $ hg cat -r 2 foo.whole ONE $ cd ..