Preparation for #865, which proposes adding a flag which outputs which
config options are used during formatting.
This PR should not make any difference to functionality. A lot of this
was search-and-replace.
Some areas worthy of review/discussion:
- The method for each config item returns a clone of the underlying
value. We can't simply return an immutable reference, as lots of
places in the code expect to be able to pass the returned value as
`bool` (not `&bool). It would be nice if the `bool` items could
return a copy, but the more complex types a borrowed reference... but
unfortunately, I couldn't get the macro to do this.
- A few places (mostly tests and `src/bin/rustfmt.rs`) were overriding
config items by modifying the fields of the `Config` struct directly.
They now use the existing `override_value()` method, which has been
modified to return a `Result` for use by `src/bin/rustfmt.rs`. This
benefits of this are that the complex `file_lines` and `write_mode`
strings are now parsed in one place (`Config.override_value`) instead
of multiple. The disadvantages are that it moves the compile-time
checks for config names to become run-time checks.
One notable feature is this this adds support for the experimental
`let x = loop { ... break $expr; }` syntax. This also includes a
test for formatting all the break and continue variations.
This commit adds a `codemap` module, and moves the `CodemapSpanUtils`
added in #857 to it. This is preparation for adding more `Codemap`
specific utilities.
Refs #434
The error handling in libsyntax changed to use a `DiagnosticBuilder`
type in the `Err` variant of `PResult`. This type has `emit()` and
`cancel()` methods. Once created, errors must be emitted or canceled; if
not, the `Drop` impl on `DiagnosticBuilder` will panic.
The first syntex_syntax release to include this change was v0.25.0. The
bump from v0.23.0 to v0.29.1 in #847 did not add any `cancel()` calls,
even though at least one was required. There may be others not caught in
this commit.
This commit adds a CodeMapSpanUtils extension trait on CodeMap, and
moves some functions to methods there:
- span_after
- span_after_last
- span_before
This better reflects them being lookup methods on the codemap.
