* Implement #warning and #error
* Fix #warning/#error in switch statements
* Fix AST printing for #warning/#error
* Add to test case
* Add extra handling to ParseDeclPoundDiagnostic
* fix dumping
* Consume the right paren even in the failure case
* Diagnose extra tokens on the same line after a diagnostic directive
libSyntax nodes don't maintain absolute source location on each
individual node. Instead, the absolute locations are calculated on
demand with a given root by accumulating the length of all the other
nodes before the target node. This bridging is important for issuing
diagnostics from libSyntax entities.
With the observation that our current implementation of the source
location calculation has multiple bugs, this patch re-implemented this
bridging by using the newly-added syntax visitor. Also, we moved the function
from RawSyntax to Syntax for better visibility.
To test this source location calculation, we added a new action in
swift-syntax-test. This action parses a given file as a
SourceFileSyntax, calculates the absolute location of the
EOF token in the SourceFileSyntax, and dump the buffer from the start
of the input file to the absolute location of the EOF. Finally, we compare
the dump with the original input to ensure they are identical.
A string interpolation expression is composed of { OpenQuote, Segments,
CloseQuote }. To represent OpenQuote, CloseQuote and StringSegment, we have to
introduce new token kinds correspondingly.
Patterns those are parsed as ExpressionPattern at first, then resolved
to actual patterns:
* OptionalPattern -> pattern '?'
* AsTypePattern -> pattern 'as' type
* EnumCasePattern -> type? '.' identifier tuple-pattern
Variable declarations are declarations led by either 'var' or 'let'. It
can contain multiple pattern bindings as children.
For patterns, this patch only creates syntax nodes for simple identifier
patterns, e.g. 'a = 3'. The rest of the pattern kinds are still left
unknown (UnknownPattern).
This patch also refactors the structure of function signature node so
that closure signature can re-use parts of function signature. For
instance, we group arrow and return type to be "ReturnClause". And we
group parenthesized parameter list to be "ParamClause".
This structure of closure signature also calls for a good way to
represent either-or node in libSyntax APIs, since we've two ways to
specify parameters in closure: one is as regular function parameter and
the other is dot-separated simple names.
