One issue with fish_add_path at the moment is that it is sometimes a bit too intransparent.
You'll try to add a path, but it won't appear - was that because it wasn't a directory,
or because it doesn't exist, or because it was already included?
If it isn't usable after, did fish_add_path not add it because of something or did something *else* remove it?
So we give more explanations - "skipping this because it's a file", "not setting anything because no paths are left to add", ...
fish_add_path can be used either interactively, in the commandline,
or in config.fish. That's its greatest strength, it's a very
DWIM-style command.
One of the compromises that entails, however, is that it can't really
be very loud about what it does. If it skips a path, it can't write a
warning because it might be used in config.fish.
But it *can* if it's used interactively. So we try to detect that case
and enable verbose mode automatically.
That means if you do
```fish
fish_add_path /opt/mytool/bin/mytool
```
it may tell you "Skipping path because it is a file instead of a
directory:".
The check isn't perfect, it goes through status current-command and
isatty, but it should be good for most cases (and be false in config.fish).
Previously, running `fish_add_path /foo /foo` would result in /foo
being added to $PATH twice.
Now we check that it hasn't already been given, so we skip the
second (and any further) occurence.
* Print message in set_fish_path -v when a path doesnt exist
* Update changelog
* Remove "; or continue"
* use printf instead of echo, avoid localizing the path
This `set -e` had a cartesian product that caused it to remove the
indexes separately, so the later indexes were off - removing the first
and then the second ends up removing the first and then the
old-*third* which is now the second.
Just quote the expansion so it runs in one go.
Fixes#7776
The case for symlinked directories being duplicated a lot isn't there,
but there *is* a usecase for adding the symlink rather than the
target, and that's homebrew.
E.g. homebrew installs ruby into /usr/local/Cellar/ruby/2.7.1_2/bin,
and links to it from /usr/local/opt/ruby/bin. If we add the target, we
would miss updates.
Having path entries that point to the same location isn't a big
problem - it's a path lookup, so it takes a teensy bit longer. The
canonicalization is mainly so paths don't end up duplicated via weird
spelling and so relative paths can be used.
This is a function you can either execute once, interactively, or
stick in config.fish, and it will do the right thing.
Some options are included to choose some slightly different behavior,
like setting $PATH directly instead of $fish_user_paths, or moving
already existing components to the front/back instead of ignoring
them, or appending new components instead of prepending them.
The defaults were chosen because they are the most safe, and
especially because they allow it to be idempotent - running it again
and again and again won't change anything, it won't even run the
actual `set` because it skips that if all components are already in.
Fixes#6960.
