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.
To construct struct syntax, this patch first specialized type
inheritance clause. For protocol's class requirement, we currently
treat it as an unknown type.
This patch also teaches SyntaxParsingContext to collect syntax nodes
from back in place. This is useful to squash multiple decl modifiers
for declarations like function. This is not used for struct declaration
because only accessibility modifier is allowed.
This patch also performs minor refactoring to align syntax parsing
context with the right scope. We start to support the generic clauses
because they are necessary pieces to construct struct or
function syntax node.
Because generic where clause doesn't coerce well to our existing syntax
context kinds, we add a new syntax context kind with this patch called
"Syntax". This context kind indicates that when error occurs, the
collection of syntax nodes falling into the context should be coerced
to UnknownSyntax.
This commit starts to support syntax nodes for @ attributes list for
declarations. These attributes don't include modifiers like "static" or
access keywords. Along with the function change, the commit refactors
some existing code to reduce duplication.
* libSyntax: Parse member access expression.
This patch uses createNodeInPlace from syntax parsing context API to
merge an expression with its suffix to create recursive nodes such as
member access expression.
Meanwhile, this patch breaks down a signed integer or float literal to a
prefix operator expression. This expression consists of two parts: an
operator and the following expression. This makes literals like "+1" or
"-1" no different from other prefix unary expressions such as "!true".
Tuple expression essentially has the same underlying structure as
function call arguments in libSyntax. However, we separate them as
different libSyntax kinds for better usability.
Different from AST, libSyntax currently allows single-child,
label-free tuple expressions (represented as ParenExpr in AST). This is
subject to change if we need to adopt the same differentiation in
libSyntax in the future.
Along with starting to support ternary expressions, this commit also
slightly changes SyntaxParsingContext APIs as follows:
1. Previously, makeNode() only supports node creation by using the nodes
from the underlying syntax token array; this commit allows it to use the nodes from
the pending syntax list as well.
2. This commit strictly limits that the pending syntax list should never
contain token syntax node.
3. The node kind test shouldn't include unknown kinds. They are noisy.
This commit also adds ArrayExpr and DictionaryExpr to the libSyntax nodes
family. Also, it refactors the original parser code for these two
expressions to better fit to the design of SyntaxParsingContext.
This commit has also fixed two crashers.
This commit teaches parser to parse two libSyntax nodes: FunctionCallArgument and
FunctionCallArgumentList. Along with the change, some libSyntax parsing infrastructure changes
as well: (1) parser doesn't directly insert token into the buffer for libSyntax node creation;
instead, when creating a simple libSyntax node like integer literal expression, parser should indicate the location of the last token in the node; (2) implicit libSyntax nodes like empty
statement list must contain a source location indicating where the implicit nodes should appear
(immediately before the token at the given location).
This commit teaches parser to generate code block syntax node. As a support for this,
SyntaxParsingContext can be created by a single syntax kind, indicating the whole context
should be parsed into a node of that given syntax. Another change is to bridge created syntax
node with the given context kind. For instance, if a statement context results into an expression
node, the expression node will be bridged to a statement by wrapping it with a ExpressionStmt
node.
* Re-apply "libSyntax: Ensure round-trip printing when we build syntax tree from parser incrementally. (#12709)"
* Re-apply "libSyntax: Root parsing context should hold a reference to the current token in the parser, NFC."
* Re-apply "libSyntax: avoid copying token text when lexing token syntax nodes, NFC. (#12723)"
* Actually fix the container-overflow issue.
