How to get hg mdiff to ignore whitespace differences? - mercurial

I recently started using mercurial. I often want to check differences between revisions while ignoring whitespace (e.g. due to running dos2unix on certain files). Now, for hg mdiff, I can do this using a modified diff command, hg wdiff, the arrangement of which is described here:
Whitespace-ignoring diffs with Mercurial
How can I do the same for hg mdiff?

You probably can't. The Mergediff extension has a very different implementation, that's likely not supported by command-line diff tools (if only because it has to compare 3 versions instead of just 2).
You could extend the Mergediff extension to have a whitespace-ignoring mode, I guess.

Related

hg automatic merges with diff3

Consider a Hg project with two central branches/clones - e.g. DEV and PRD. When someone pushes a hotfix to PRD, an automated script on the central server goes to DEV and pulls the new changes. It then tries to merge the hotfix into DEV.
The problem is that the merge tool integrated into Hg is terrible - as soon as there are parallel changes to the same file it will fail. Take the following example:
parent:3,7c
four
five
six
seven
child1:3,7c
four
five5
six6
seven7
child2:3,7c
fourmore
five
six
more
seven
As you can see, there are no actual conflicts here. If we do the merge locally with kdiff, it solves this simple case without user input!
I'd like a way to get the central server to manage these cases. I thought of using kdiff3 in silent mode, but I can't install kdiff3 on it (it's a CLI only system that we don't even have admin access to), but maybe there is a way to plug diff3 into hg merge so it can resolve simple cases like this? I tried setting "[ui] /n merge = diff3" in the hgrc, but it just spits out the three versions to stdout. Am i missing some additional configuration? Or is there an easier/better tool?
Thanks a lot
To use diff3 as your merge tool, you need to add
[merge-tools]
diff3.args = $local $base $other -m > $output
to your configuration file. You can set the priority if needed, see the wiki. You'll also find more complicated recipes for using diff3 there.
However, I tested how diff3 treats your scenario with edits on adjacent lines, and just like Mercurial, it also refused to merge this cleanly. Different merge tools have different thresholds for what they consider a "conflict" and it seems that KDiff3 is more forgiving than Mercurial and diff3.
I suggest that you let the developer who makes the hotfix on PRD be responsible for merging it into DEV locally where he has access to tools like KDiff3. Automated merging on a server is generally considered to be bad — merges should be verified just a little by a human before you commit them. It's not much extra work after having made the hotfix.

using hg revert to revert a group of files in Mercurial

I'm using Mercurial to read and debug a complex project, and my modify of the project can be divided into different group of files clearly. For example, if I modified four files
src1.cc src1.hh src2.cc src2.hh
It's apparent that I can divide them into two file groups such as group src1 includes src1.cc src1.hh and group src2 includes src2.cc src2.hh.
I'm wondering if I can revert a group of files by a simple command like 'hg revert group-name-alias' instead of listing all the filename of the group, which is a awful idea if I have modified many files?
Any help really appreciated!
From what I can understand of your use-case, you can:
Use patterns in the hg revert command. This means that you can
run hg revert src1* to revert all the first group.
Most probably, though, your stuff is in sub-folders and thankfully
you can specify a parent folder to the revert command.
So say your files are really like: foo/src1.cc, foo/src1.hh,
bar/src2.cc, bar/src2.hh. In that case, you can revert all the
second group with hg revert bar, assuming you're in the top folder.
If you're already in the bar folder, you can run hg revert ..
You can specify several patterns.
Use Mercurial queues if each one of your "file groups" is also
a different unit of work (a different bug fix or feature). This is not
so desirable if all files belong to the same unit of work, though.
No. To the best of my knowledge, Mercurial has no mechanism for grouping files.
You could do some trickery with aliases ([alias] revert-group-name = revert src2.cc src2.hh in ~/.hgrc), but aliases can only be prefixes, and can't perform variable expansions.
If your files are simple enough, you could use shell globbing (hg revert src2*), or a shell variable (GROUP_NAME="src2.cc src2.hh", then hg revert $GROUP_NAME).
You could also consider writing a small Mercurial extension. If you know Python, they don't take very long (my first took me about 30 minutes).
If the filenames meet patterns, you can use that pattern:
hg revert src1*
or
hg revert src1*.*
If those files are in a specific directory, you can do this:
hg revert dir\*
If the directory is more than one level deep and you want to get that directory and all its subdirectories, you can use this version of that commend:
hg revert dir\**\*

How resolve this Mercurial conflict?

I'm frustrated with Mercurial and Python since it makes easy things difficult. I have a trivial conflict and since Mercurial does not give any suggestion what to do I don't know even how to resolve this trivial file conflict:
The conflict is trivial but if I can't resolve this I can't resolve anything complicated either. Can I just edit the file to a way I want and commit it again from anywhere? Should I run hg merge? Why can't Mercurial even let me choose a version to keep? Why is something trivial near impossible to do without digging through 1000 poorly written manpages?
You need to look at the KDiff3 documentation, in particular the section on merging and the output window. To resolve the conflict, you need to decide if live or january is the right choice for the line. That decision is yours to make, no tool can know if you meant one or the other.
In KDiff3, you press Ctrl + 2 to select live, press Ctrl + 3 to select january or right-click in the margin of the bottom window and select the line you want. You can also click in the bottom window and edit the line manually.
Mercurial let's you configure your merge tool any way you like. TortoiseHg ships with a default configuration that puts KDiff3 in the top of the list, but you can use another tool if you like. A merge tool is really just a program that accepts four filenames: the three files to compare (base, parent 1, parent 2) and an output file name.
To resolve conflicts on the command-line you need to launch a suitable command-line three-way merge tool. You can for example merge with vim if you like. (I'm afraid I don't know anything about vimdiff, I use KDiff3 myself.)
If you don't like to see merge tools pop up, then you can set
[ui]
merge = internal:merge
to make Mercurial use the internal three-way merger only. It will merge files fine when the edits are not in conflicts. When there is a conflict, the file is marked as "unresolved" and conflict markers are stored in the file.
You then need to edit the file by hand to get the version you want. You can also re-merge and pick either the local (your) version:
$ hg resolve --tool internal:local your-file
or the other version:
$ hg resolve --tool internal:other your-file
You restart the merge completely with hg resolve your-file. The file needs to be marked "resolved" before you can commit it. This is done with hg resolve --mark your-file. See hg resolve --list for the status of the current merge.
Base is the previous version in your local system,
Parent 1 is your current changes,
parent 2 is the file from server.
If you need your changes need to be checked in, select B everywhere in the merge menu.
If you want the latest server version in your local machine, select C everywhere in the merge menu

Why doesn't Mercurial Eclipse auto-add files like Subclipse?

What is the use case for this behavior, which has made my work unavailable from one location to the next on a dozen occasions? Why is hg like this? How am I "not in the know"?
Hg behaves like svn in this case: it only tracks the files that were explicitly added with svn add or hg add command.
But eclipse plugins behave differently. Why - you could ask their authors.
Zerkms says it as it is - the Eclipse plugin follows the Mercurial standard behaviour.
However, you can enable the option 'preselect tracked files in commit dialog' in the preferences to get default-to-add on commit. :)

Mercurial performing binary comparison for certain file types [duplicate]

This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
Why does Mercurial think my SQL files are binary?
I've recently started using Mercurial and when I reverted one of my .SQL files, Mercurial performed a binary comparison. This obviously limits the visibility of the changes that were made, as there is no diff.
Is there an option to set file types to do a string compare?
I'm using Tortioise Hg 0.8.1 with Mercurial 1.3.1.
Mercurial doesn't actually handle text and binaries at all differently with respect to actual storage. It does however try to guess "would visually showing this diff be meaningful" when asked to show a diff to a user with hg diff, hg log -p, or when viewing a changeset in the web interface. When it's trying to make the "should I show this as if it's text" decision the test applied is "Is there a NUL byte (0x00) within the first 1000 bytes of a file.
So your file isn't being treated any differently except in how it's displayed to user output, but if you can find a NUL byte in there you can probably get that to stop too.
Alternately, the extdiff extension can be used to take total control of how diffs are displayed.
I don't know about the graphical part of TortoiseHg, but if you use the command line, then the --text flag to hg diff should do the trick: it makes Mercurial treat all files as text.
You should try adding these lines to ~/.hgrc:
[diff]
git=1
The git diff format works for binary files.