The current implementation didn't reload the theme if no no theme was
explicitly configured (so the default theme was used). This commit
brings `refresh_theme` in line with the initialization code.
Add new theme highlight keys, for setting the colour of the breakpoint
character and the current line at which execution has been paused at.
The two new keys are `ui.highlight.frameline` and `ui.debug.breakpoint`.
Highlight according to those keys, both the line at which debugging
is paused at and the breakpoint indicator.
Add an indicator for the current line at which execution is paused
at, themed by the `ui.debug.active` theme scope. Update various themes
to showcase how the new functionality works.
Better icons are dependent on #2869, and as such will be handled in the
future, once it lands.
Closes: #5952
Signed-off-by: Filip Dutescu <filip.dutescu@gmail.com>
While scrolling (with the `scroll`) command scrolloff was calculated
slightly differently than in `ensure_cursor_in_view` which could cause
the cursor to get stuck while scrolling
Virtual text lines (either caused by softwrapped inlay hints that take
multiple or line annotations) currently block scrolling downwards.
if the visual offset passed to char_idx_at_visual_offset or
visual_offset_from_block is within a virtual text line then the char
position before the virtual text and a visual offset are returned.
We previously ignored that visual offset and as a result the cursor
would be stuck at the start of the virtual text. This commit fixes
that by simply moving the cursor to the next char (so past the virtual
text) if this visual offset is non-zero
* helix-term: send the STOP signal to all processes in the process group
From kill(3p):
If pid is 0, sig shall be sent to all processes (excluding an unspecified set
of system processes) whose process group ID is equal to the process group ID
of the sender, and for which the process has permission to send a signal.
This fixes the issue of running `git commit`, attempting to suspend
helix with ^Z, and then not regaining control over the terminal and
having to press ^Z again.
* helix-term: use libc directly to send STOP signal
* helix-term: document safety of libc::kill
* helix-term: properly handle libc::kill's failure
I misread the manpage for POSIX `kill` -- it returns `-1` in
the failure case, and sets `errno`, which is retrieved via
`std::io::Error::last_os_error()`, has its string representation printed
out, and then exits with the matching status code (or 1 if, for whatever
reason, there is no matching status code).
* helix-term: expand upon why we need to SIGSTOP the entire process group
Also add a link back to one of the upstream issues.
* misc: missing inline, outdated link
* doc: Add new theme keys and config option to book
* fix: don't panic in Tree::try_get(view_id)
Necessary for later, where we could be receiving an LSP response
for a closed window, in which case we don't want to crash while
checking for its existence
* fix: reset idle timer on all mouse events
* refacto: Introduce Overlay::new and InlineAnnotation::new
* refacto: extract make_job_callback from Context::callback
* feat: add LSP display_inlay_hint option to config
* feat: communicate inlay hints support capabilities of helix to LSP server
* feat: Add function to request range of inlay hint from LSP
* feat: Save inlay hints in document, per view
* feat: Update inlay hints on document changes
* feat: Compute inlay hints on idle timeout
* nit: Add todo's about inlay hints for later
* fix: compute text annotations for current view in view.rs, not document.rs
* doc: Improve Document::text_annotations() description
* nit: getters don't use 'get_' in front
* fix: Drop inlay hints annotations on config refresh if necessary
* fix: padding theming for LSP inlay hints
* fix: tracking of outdated inlay hints should not be dependant on document revision (because of undos and such)
* fix: follow LSP spec and don't highlight padding as virtual text
* config: add some LSP inlay hint configs
Multicursor completions may overlap and therefore overlapping
completions must be dropped to avoid crashes. Furthermore, multicursor
edits might simply be out of range if the word before/after the cursor
is shorter. This currently leads to crashes, instead these selections
are now also removed for completions.
This commit also significantly refactors snippet transaction generation
so that tabstops behave correctly with the above rules. Furthermore,
snippet tabstops need to be carefully mapped to ensure their position
is correct and consistent with our selection semantics. Finally,
we now keep a partially updated Rope while creating snippet
transactions so that we can fill information into snippets that
depends on the position in the document.
Most LSPs will complete case-insensitive matches, particularly from
lowercase to uppercase. In some cases, notably Pyright, this is given
as a simple insert text instead of TextEdit. When this happens, the
prefix text was left unedited.
* Generalised to multiple runtime directories with priorities
This is an implementation for #3346.
Previously, one of the following runtime directories were used:
1. `$HELIX_RUNTIME`
2. sibling directory to `$CARGO_MANIFEST_DIR`
3. subdirectory of user config directory
4. subdirectory of path to helix executable
The first directory provided / found to exist in this order was used as a
root for all runtime file searches (grammars, themes, queries).
This change lowers the priority of `$HELIX_RUNTIME` so that the user
config runtime has higher priority. More significantly, all of these
directories are now searched for runtime files, enabling a user to override
default or system-level runtime files. If the same file name appears
in multiple runtime directories, the following priority is now used:
1. sibling directory to `$CARGO_MANIFEST_DIR`
2. subdirectory of user config directory
3. `$HELIX_RUNTIME`
4. subdirectory of path to helix executable
One exception to this rule is that a user can have a `themes`
directory directly in the user config directory that has higher piority
to `themes` directories in runtime directories. That behaviour has been
preserved.
As part of implementing this feature `theme::Loader` was simplified
and the cycle detection logic of the theme inheritance was improved to
cover more cases and to be more explicit.
* Removed AsRef usage to avoid binary growth
* Health displaying ;-separated runtime dirs
* Changed HELIX_RUNTIME build from src instructions
* Updated doc for more detail on runtime directories
* Improved health symlink printing and theme cycle errors
The health display of runtime symlinks now prints both ends of the
link.
Separate errors are given when theme file is not found and when the
only theme file found would form an inheritence cycle.
* Satisfied clippy on passing Path
* Clarified highest priority runtime directory purpose
* Further clarified multiple runtime details in book
Also gave markdown headings to subsections.
Fixed a error with table indentation not building
table that also appears present on master.
---------
Co-authored-by: Paul Scott <paul.scott@anu.edu.au>
Co-authored-by: Blaž Hrastnik <blaz@mxxn.io>
* Fix#6092
Cause were some incorrect assumptions that missed an edge case in the
`Selection.contains()` calculation. Tests were added accordingly.
* Fix Selection.contains() edge-case handling.
Removing the len check short-circuit was the only thing needed as
pointed out by @dead10ck.
Repeating completions currently crates a savepoint when a completion
popup was triggered (so after the request completed). Just like for
normal completions the savepoint must be created at the request.
The occurrence of the completion request was previously not saved in
`last_insert`. To that end a new `InsertEvent::RequestCompletion`
variant has been added. When replayed this event creates a snapshot
that is "actived" by the `TriggerCompletion` event and subsequently
used during any `InsertEvent::CompletiuonApply` events.
Completion requests are computed asynchronously to avoid common micro
freezes while editing. This means that once a completion request
completes, the state of the editor might have changed. Currently,
there is a check to ensure we are still in insert mode. However,
we also need to ensure that the view and document hasn't changed
to avoid accidentally using a savepoint with the wrong view/document.
Furthermore, the editor might request a new completion while the
previous completion request hasn't complemented yet. This can
lead to weird flickering or an outdated completion request replacing
a newer completion that has already completed (the LSP server
is not required to process completion requests in order). This change
also needed to ensure determinism/linear ordering so that completion
popup always correspond to the last completion request.
Fixing autocomplete required moving the document savepoint before the
asynchronous completion request. However, this in turn causes new bugs:
If the completion popup is open, the savepoint is restored when the
popup closes (or another entry is selected). However, at that point
a new completion request might already have been created which
would have replaced the new savepoint (therefore leading to incorrectly
applied complies).
This commit fixes that bug by allowing in arbitrary number of
savepoints to be tracked on the document. The savepoints are reference
counted and therefore remain valid as long as any reference to them
remains. Weak reference are stored on the document and any reference
that can not be upgraded anymore (hence no strong reference remain)
are automatically discarded.
Currently, the selection is not saved/restored when completion
checkpoints are applied. This is usually fine because undoing changes
usually restores maps selections back in insert mode. But this is not
always the case and especially problematic in the presence of
multi-cursor completions (since completions are applied relative to
the selection/cursor) and snippets (which can change the selection)
* LSP: Support textDocument/prepareRename
'textDocument/prepareRename' can be used by the client to ask the
server the range of the symbol under the cursor which would be changed
by a subsequent call to 'textDocument/rename' with that position.
We can use this information to fill the prompt with an accurate prefill
which can improve the UX for renaming symbols when the symbol doesn't
align with the "word" textobject. (We currently use the "word"
textobject as a default value for the prompt.)
Co-authored-by: Michael Davis <mcarsondavis@gmail.com>
* clippy fixes
* rustfmt
* Update helix-term/src/commands/lsp.rs
Co-authored-by: Michael Davis <mcarsondavis@gmail.com>
* Update helix-term/src/commands/lsp.rs
Co-authored-by: Michael Davis <mcarsondavis@gmail.com>
* fix clippy from suggestions
* Update helix-term/src/commands/lsp.rs
Co-authored-by: Michael Davis <mcarsondavis@gmail.com>
---------
Co-authored-by: Michael Davis <mcarsondavis@gmail.com>
* use max_line_width + 1 during softwrap to account for newline char
Helix softwrap implementation always wraps lines so that the newline
character doesn't get cut off so he line wraps one chars earlier then
in other editors. This is necessary, because newline chars are always
selecatble in helix and must never be hidden.
However That means that `max_line_width` currently wraps one char
earlier than expected. The typical definition of line width does not
include the newline character and other helix commands like `:reflow`
also don't count the newline character here.
This commit makes softwrap use `max_line_width + 1` instead of
`max_line_width` to correct the impedance missmatch.
* fix typos
Co-authored-by: Jonathan Lebon <jonathan@jlebon.com>
* Add text-width to config.toml
* text-width: update setting documentation
* rename leftover config item
* remove leftover max-line-length occurrences
* Make `text-width` optional in editor config
When it was only used for `:reflow` it made sense to have a default
value set to `80`, but now that soft-wrapping uses this setting, keeping
a default set to `80` would make soft-wrapping behave more aggressively.
* Allow softwrapping to ignore `text-width`
Softwrapping wraps by default to the viewport width or a configured
`text-width` (whichever's smaller). In some cases we only want to set
`text-width` to use for hard-wrapping and let longer lines flow if they
have enough space. This setting allows that.
* Revert "Make `text-width` optional in editor config"
This reverts commit b247d526d69adf41434b6fd9c4983369c785aa22.
* soft-wrap: allow per-language overrides
* Update book/src/configuration.md
Co-authored-by: Pascal Kuthe <pascal.kuthe@semimod.de>
* Update book/src/languages.md
Co-authored-by: Pascal Kuthe <pascal.kuthe@semimod.de>
* Update book/src/configuration.md
Co-authored-by: Pascal Kuthe <pascal.kuthe@semimod.de>
---------
Co-authored-by: Pascal Kuthe <pascal.kuthe@semimod.de>
Co-authored-by: Jonathan Lebon <jonathan@jlebon.com>
Co-authored-by: Alex Boehm <alexb@ozrunways.com>
Co-authored-by: Blaž Hrastnik <blaz@mxxn.io>
* Do not add intermediate lines to jumplist with :<linenum> command.
* Revert jumplist index changes.
* Reduce calculations during update cycle.
* Use jumplist for undo, set jumplist before preview.
* remove some debug logging
* Revert "remove some debug logging"
This reverts commit 5772c4327e7121c53ea0726a4d7333ae1c413ffb.
* Revert "Use jumplist for undo, set jumplist before preview."
This reverts commit f73a1b29824feaf16477b9df547fb28d9db81923.
* Add last_selection, update implementation.
* @pascalkuthe initial feedback
* Ensure ":goto 123" keybinding works as expected.
* fix clippies, prefer expect() for expect last_selection state
This fixes blank row text in a DynamicPicker which is initially given
no options. This can happen for language servers which respond to
the workspace symbol request for an empty query with an empty list
of symbols, and that behavior is somewhat common since returning all
symbols as the spec suggests is very expensive.
For empty options, `Picker::new` calculated the widths of each column
as 0. We can recalculate the column widths when the new options are
set to fix this. This refactor is also a good opportunity to formalize
setting new options on a picker: besides setting the new options and
calculating column widths we also want to reset the cursor and rescore
the options.
Previously we did not respond to malformed or unhandled LSP requests.
The JSONRPC spec says that all non-notification requests must have
responses:
> When a rpc call is made, the Server MUST reply with a Response,
> except for in the case of Notifications
(Note that Helix is the "Server" in this case. Also from the spec:
"The Server is defined as the origin of Response objects and the
handler of Request objects.")
So this change sends error replies for requests which can't be parsed
or handled. Request IDs are also now added to the log messages for
unhandled requests.
This moves the `Application::claim_term` and
`helix-term::application::restore_term` functions into the helix-tui
crate. How the terminal should be claimed and restored is a TUI concern
and is implemented differently through different TUI backends.
This cleans out a lot of crossterm and TUI code in Application and
makes it easier to modify claim/restore based on information we query
from the terminal host. The child commit will take advantage of this
to cache the check for whether the host terminal supports the keyboard
enhancement protocol. Without this change, caching that information
takes much more code which is not easily reusable for anything else.
The code to restore the terminal is somewhat duplicated by this patch:
we want to restore the terminal in cases of panics. Panic handler hooks
must live for `'static` and the Application's terminal does not.
This refactors the snippet logic to be largely unaware of the rest of
the document. The completion application logic is moved into
generate_transaction_from_snippet which is extended to support
dynamically computing replacement text.
When accepting a snippet completion we automatically delete the
placeholders for now as doing so manual is quite cumbersome. In the
future we should keep these as a mark + virtual text that is
automatically removed once the cursor moves there.
Add a restart debug session command, which would issue a
[Restart Request][1], if the debugger supports it and a session is
running. It uses the same arguments and requests used to start the
initial session, when recreating it.
It builds upon #5532, making use of the changes to the termination
workflow of a session.
[1]: https://microsoft.github.io/debug-adapter-protocol/specification#Requests_RestartCloses: #5594
Signed-off-by: Filip Dutescu <filip.dutescu@gmail.com>
* Fix lack of space for popup crash
* Fix saturating -> wrapping
* Fix wrapping -> saturating (I am an idiot)
* Remove useless "mut" in helix-tui/src/buffer.rs
Co-authored-by: Michael Davis <mcarsondavis@gmail.com>
* Remove redundant bound-check
* Return bound-check back
* Add bound-check for set_style
* Remove set_style bound-check
* Revert bound-check
---------
Co-authored-by: Michael Davis <mcarsondavis@gmail.com>
This is a workaround for a freeze when suspending Helix with C-z on
non-Windows systems. The check for the keyboard enhancement protocol
locks up crossterm's internal event reading/polling system by trying to
set up multiple concurrent readers. `input_stream.next()` sets up one
reader looking for regular crossterm events while the
`supports_keyboard_enhancement` query sets up another looking for
internal events. The latter hangs for two seconds or until the former
yields an event. By handling signals first we don't lock up the mutex
by trying to read keyboard events.
Since crossterm 0.26.x, we receive press/release keyboard events on
Windows always. We can ignore the release events though to emulate
the behavior of keyboard input on Windows on crossterm 0.25.x.
When the Kitty Keyboard Protocol is enabled, S-backspace is
distinguished from backspace with no modifiers. This is awkward when
typing because it's very easy to accidentally hold shift and press
backspace temporarily when typing capital letters.
Kakoune (which is also a Kitty Keyboard Protocol application) treats
S-backspace as backspace too:
3150e9b3cd/src/input_handler.cc (L1275)
Check if the stack frames contain the thread id and the frame before
trying to get the frame id. If case any of the two fails to be
found, provide the user with messages to inform them of the issue and
gracefully return.
Closes: #5625
Signed-off-by: Filip Dutescu <filip.dutescu@gmail.com>
Send a `Disconnect` DAP request if the `Terminated` event is received.
According to the specification, if the debugging session was started by
as `launch`, the debuggee should be terminated alongside the session. If
instead the session was started as `attach`, it should not be disposed of.
This default behaviour can be overriden if the `supportTerminateDebuggee`
capability is supported by the adapter, through the `Disconnect` request
`terminateDebuggee` argument, as described in
[the specification][discon-spec].
This also implies saving the starting command for a debug sessions, in
order to decide which behaviour should be used, as well as validating the
capabilities of the adapter, in order to decide what the disconnect should
do.
An additional change made is handling of the `Exited` event, showing a
message if the exit code is different than `0`, for the user to be aware
off the termination failure.
[discon-spec]: https://microsoft.github.io/debug-adapter-protocol/specification#Requests_DisconnectCloses: #4674
Signed-off-by: Filip Dutescu <filip.dutescu@gmail.com>
The completion component has a separate branch for handling the
Escape key but it can use the `ignore_escape_key` helper added for
signature-help instead.
This should not cause a behavior change - it's just cleaning up the
completion component.
* feat(ui): deprecated completions
Mark deprecated completions using strike-through
(CROSSED_OUT modifier). The deprection information
is taken either from the `deprecated` field of the
completion item or from the completion tags.
The field seems to be the older way of passing
the deprecated information and it was already
marked as deprecated for Symbol. In completion
item the field is still valid but it seems that
the LSP is moving in the general direction of using
tags for this kind of information and as such
relying on tags as well seems reasonable and
future-proof.
So far LSP always required that `PositionEncoding.characters` is an
UTF-16 offset. Now that LSP 3.17 is available in `lsp-types` request
the server to send char offsets (UTF-32) or byte offsets (UTF-8)
instead. For compatability with old servers, UTF-16 remains as the
fallback as required by the standard.
* Make `m` textobject look for pairs enclosing selections
Right now, this textobject only looks for pairs that surround the
cursor. This ensures that the pair found encloses each selection, which
is likely to be intuitively what is expected of this textobject.
* Simplification of match code
Co-authored-by: Michael Davis <mcarsondavis@gmail.com>
* Adjust logic for ensuring surround range encloses selection
Prior, it was missing the case where the start of the selection came
before the opening brace. We also had an off-by-one error where if the
end of the selection was on the closing brace it would not work.
* Refactor to search for the open pair specifically to avoid edge cases
* Adjust wording of autoinfo to reflect new functionality
* Implement tests for surround functionality in new integration style
* Fix handling of skip values
* Fix out of bounds error
* Add `ma` version of tests
* Fix formatting of tests
* Reduce indentation levels for readability, and update comments
* Preserve each selection's direction with enclosing pair surround
* Add test case for multiple cursors resulting in overlap
* Mark known failures as TODO
* Make tests multi-threaded or they fail
* Cargo fmt
* Fix typos in integration test comments
---------
Co-authored-by: Michael Davis <mcarsondavis@gmail.com>
Example:
```
test
testitem
```
Select line 2 with x, then type Alt-C; Helix will go into an infinite
loop. The saturating_sub keeps the head_row and anchor_row pinned at 0,
and a selection is never made since the first line is too short.
This matches the behavior from 42ad1a9e04
but for the first and last change. The selection rules are the same
as for goto_next/prev_change: additions and modifications select the
added and modified range while deletions are represented with a point.
This will allow testing more of the code base, as well as enable UI-
specific testing.
Debug mode builds are prohibitively slow for the tests, mostly
because of the concurrency write tests. So there is now a profile for
integration tests that sets the optimization level to 2 for a few helix
crates, and lowers the number of rounds of concurrent writes to 1000.
* hide duplicate symlinks from the picker
* Apply suggestions from code review
Co-authored-by: g-re-g <123515925+g-re-g@users.noreply.github.com>
* minor stylistic fix
Co-authored-by: Michael Davis <mcarsondavis@gmail.com>
---------
Co-authored-by: g-re-g <123515925+g-re-g@users.noreply.github.com>
Co-authored-by: Michael Davis <mcarsondavis@gmail.com>
This change makes `ms<ret>` work similarly to `t<ret>` and related
find commands: when the next event is a keypress of Enter, surround
the selection with the document's line-endings.
* rework positioning/rendering, enables softwrap/virtual text
This commit is a large rework of the core text positioning and
rendering code in helix to remove the assumption that on-screen
columns/lines correspond to text columns/lines.
A generic `DocFormatter` is introduced that positions graphemes on
and is used both for rendering and for movements/scrolling.
Both virtual text support (inline, grapheme overlay and multi-line)
and a capable softwrap implementation is included.
fix picker highlight
cleanup doc formatter, use word bondaries for wrapping
make visual vertical movement a seperate commnad
estimate line gutter width to improve performance
cache cursor position
cleanup and optimize doc formatter
cleanup documentation
fix typos
Co-authored-by: Daniel Hines <d4hines@gmail.com>
update documentation
fix panic in last_visual_line funciton
improve soft-wrap documentation
add extend_visual_line_up/down commands
fix non-visual vertical movement
streamline virtual text highlighting, add softwrap indicator
fix cursor position if softwrap is disabled
improve documentation of text_annotations module
avoid crashes if view anchor is out of bounds
fix: consider horizontal offset when traslation char_idx -> vpos
improve default configuration
fix: mixed up horizontal and vertical offset
reset view position after config reload
apply suggestions from review
disabled softwrap for very small screens to avoid endless spin
fix wrap_indicator setting
fix bar cursor disappearring on the EOF character
add keybinding for linewise vertical movement
fix: inconsistent gutter highlights
improve virtual text API
make scope idx lookup more ergonomic
allow overlapping overlays
correctly track char_pos for virtual text
adjust configuration
deprecate old position fucntions
fix infinite loop in highlight lookup
fix gutter style
fix formatting
document max-line-width interaction with softwrap
change wrap-indicator example to use empty string
fix: rare panic when view is in invalid state (bis)
* Apply suggestions from code review
Co-authored-by: Michael Davis <mcarsondavis@gmail.com>
* improve documentation for positoning functions
* simplify tests
* fix documentation of Grapheme::width
* Apply suggestions from code review
Co-authored-by: Michael Davis <mcarsondavis@gmail.com>
* add explicit drop invocation
* Add explicit MoveFn type alias
* add docuntation to Editor::cursor_cache
* fix a few typos
* explain use of allow(deprecated)
* make gj and gk extend in select mode
* remove unneded debug and TODO
* mark tab_width_at #[inline]
* add fast-path to move_vertically_visual in case softwrap is disabled
* rename first_line to first_visual_line
* simplify duplicate if/else
---------
Co-authored-by: Michael Davis <mcarsondavis@gmail.com>
The new version of the `toml` crate is based on `toml_edit` and does
not support zero copy deserialization anymore. So we need to deserialize
`String` instead of `&str` in the keympa
increment/decrement (C-a/C-x) had some buggy behavior where selections
could be offset incorrectly or the editor could panic with some edits
that changed the number of characters in a number or date. These stemmed
from the automatic jumping behavior which attempted to find the next
date or integer to increment. The jumping behavior also complicated the
code quite a bit and made the behavior somewhat difficult to predict
when using many cursors.
This change removes the automatic jumping behavior and only increments
or decrements when the full text in a range of a selection is a number
or date. This simplifies the code and fixes the panics and buggy
behaviors from changing the number of characters.
After changes in #5239, the loaded configuration wasn't stored,
resulting in a success message even if the instance kept the previous
configuration values.
Commit 1b89d3e535 introduced a regression
where opening a new file would no longer work, because attempting to
canonicalize its path would lead to a "No such file or directory"
error. Fall back to opening a new file when encountering an error to
fix this case.
This commit addresses issue 5193, where the author
requested that the name of the binary needed is printed along
with the rest of the health information.
This commit adds a format! macro which formats in the name of the
binary and then it will be printed along with the rest of the
debug information. The value in cmd is referenced to the call
to which, and then consumed upon the call to format!
This roughly matches the behavior of the diagnostic picker: when
jumping to a diagnostic with `[d`/`]d`/`[D`/`]D`, the range of the
diagnostic is selected instead of the start point.
A language server might send None as the response to workspace symbols.
We should treat this as the empty Vec rather than the server sending
an error status. This fixes the interaction with gopls which uses
None to mean no matching symbols.
If the new results shown by the picker select a file that hasn't been
previewed before, the idle timeout would not trigger highlighting on
that file. With this change, we reset the idle timeout and allow that
file to be highlighted on the next idle timeout event.
This change uses the idle-timeout event to trigger fetching new results
in the DynamicPicker, so idle-timeout becomes a sort of debounce. This
prevents querying the language server overly aggressively.
Most language servers limit the number of workspace symbols that
are returned with an empty query even though all symbols are
supposed to be returned, according to the spec (for perfomance
reasons). This patch adds a workspace symbol picker based on a
dynamic picker that allows re-requesting the symbols on every
keypress (i.e. when the picker query text changes). The old behavior
has been completely replaced, and I have only tested with
rust-analyzer so far.
The error messages for a theme that failed to be deserialized (or
otherwise failed to load) were covered up by the context/with_context
calls:
* The log message for a bad theme configured in config.toml would only
say "Failed to deserilaize theme"
* Selecting a bad theme via :theme would show "Theme does not exist"
With these changes, we let the TOML deserializer errors bubble up, so
the error messages can now say the line number of a duplicated
key - and that key's name - when a theme fails to load because of a
duplicated key.
Providing a theme which does not exist to :theme still gives a helpful
error message: "No such file or directory."
* Reset mode when changing buffers
This is similar to the change in
e4c9d4082a: reset the editor to normal
mode when changing buffers. Usually the editor is already in normal
mode but it's possible to setup insert-mode keybindings that change
buffers.
* Move normal mode entering code to Editor
This should be called internally in the Editor when changing documents
(Editor::switch) or changing focuses (Editor::focus).
