As mentioned in 04c913427 (Limit command line rendering to $LINES
lines, 2024-10-25) our rendering breaks when the command line overflows
the screen and we have a pager search field.
Let's also apply the overflow logic in this case.
Note that the search field still works, it's just not visible.
In future we should maybe show a small search field (~4 lines) in
this case (removing 4 screen lines worth of command line). But again,
this is not really important.
The test case shows that the pager rendering is not quite right. It renders
'{\', leaving out the newline. This rendering is ambiguous.
Let's fix it by rendering \n as control picture, like we do for other control
characters in the pager.
Given
$ echo {\
C
where C is the cursor.
Completions have prefix "{\\\n".
Since \n has a wcwidth of -1, this line always fails
let prefix_len = usize::try_from(fish_wcswidth(&self.prefix));
This triggers uncovers a regression in 43e2d7b48 (Port pager.cpp, 2023-12-02),
where we end up computing comp_width=0 for all completions.
Fix this. Test in the next commit.
The C++ version added the prefix width only if the completion had a valid
width. That seems wrong, let's do it always (if the prefix width is valid).
Multiline search strings are weirdly broken (inserting control characters
in the command line) and probably not very useful anyway.
On the other hand I often want to compose a multi-line command
from single-line commands I ran previously.
Let's support this case by limiting the initial search string to the current
line; and replace only that line.
Alternatively this could operate on jobs (that is, replace a surrounding
"foo | bar") instead of using line boundaries.
