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    <p>You can't get there from here (as the fellow giving directions said). More precisely, it does not make sense.</p> <p>The problem is that <code>git merge --squash</code> does not actually do a merge. Suppose your branch history looks like this, for instance (with branches <code>topic</code> and <code>devel</code>):</p> <pre><code> H ⬅ I ⬅ J &lt;-- topic ⬋ ⬅ F ⬅ G ⬉ K ⬅ L &lt;-- devel </code></pre> <p>If you check out <code>devel</code> and merge <code>topic</code> you get a new merge commit <code>M</code> that contains the result of the merge, and <code>M</code> has two parents:</p> <pre><code> H ⬅ I ⬅ J &lt;-- topic ⬋ ⬆ ⬅ F ⬅ G ⬆ ⬉ ⬆ K ⬅ L ⬅ M &lt;-- devel </code></pre> <p>But if you use <code>git merge --squash topic</code> you get, instead, a new commit (let's label it <code>S</code> for squash):</p> <pre><code> H ⬅ I ⬅ J &lt;-- topic ⬋ ⬅ F ⬅ G ⬉ K ⬅ L ⬅ S &lt;-- devel </code></pre> <p>where (as you already noted) the <em>contents</em> (the tree) of commit <code>S</code> makes all the files come out the same as they would in commit <code>M</code>. But there's no back-link (parent arrow) from S to <code>topic</code>. It's not a merge at all, it's just taking all the changes from <code>topic</code>, squashing them into a single change, and adding that as an entirely independent commit.</p> <p>Now, the other thing about <code>git merge --squash</code> is that it does not make the final commit. So you could create the <code>.git</code> files that git would on a "regular" merge, and do a commit that has the two parents you'd get on a "real" merge. And then you'd get ... exactly what you get if you run <code>git merge topic</code>, a commit (label it <code>S</code> or <code>M</code>, it does not matter) that has the same tree again, but now has two parent-arrows, pointing to <code>L</code> and <code>J</code>, just like <code>M</code>.</p> <p>In fact, running <code>git merge --squash</code> is almost exactly the same as running <code>git merge --no-commit</code>, except for the tracing files left behind when the merge is done (<code>git commit</code> uses some of these to set up the parents). The <code>squash</code> version does not write to <code>.git/MERGE</code>, <code>.git/MERGE_HEAD</code>, and <code>.git/MERGE_MODE</code>. (It does create <code>.git/MERGE_MSG</code>, the same as <code>git merge --no-commit</code>, and it also creates <code>.git/SQUASH_MSG</code>.)</p> <p>So, basically, you have your choice: a real merge (two or more parents on the final commit), or a squash (same tree-combining mechanisms, but only one parent on the final commit). And, since <code>git branch --merged</code> works by looking at the "parent arrows" of each commit stored in the repository, only a real merge is really a merge, so only a real merge can be discovered later by <code>git branch</code>.</p>
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    1. POGit branch --merged / --no-merged and --squash option
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    1. UStorek
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      1. VTUpMod
    1. COYour arrows(?) between commits in your graph do not render correctly in all browsers / operating systems. I see a question mark.
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      1. USEdward Thomson
    2. COGood answer, thank you for the explanation. I thought git would be able to squash the commit and still perform a three-way merge, oh well. I feel that `git merge --squash` is slightly misleading; I would have opted for a dedicated `git squash`.
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      1. USEdwardGarson
    3. CO@EdwardThomson: yes, I tried some arrows. I imagine it's more a font thing than browser and/or OS though. Oh well, I'll go back to plain old ASCII for the next diagram :-)
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