[SwiftSyntax] Add an API to enable or disable bare slash regex literals from SwiftSyntax

This adds C functions that can be called from SwiftSyntax to enable or disable bare slash regex parsing.

It also adds a function to set the Swift language version - while this is not of top priority at the moment it will become important once we introduce a new language mode again.

rdar://93750821

Author: ahoppen

include/swift-c/SyntaxParser/SwiftSyntaxParser.h

@@ -93,6 +93,15 @@ swiftparse_parser_create(void);
 SWIFTPARSE_PUBLIC void
 swiftparse_parser_dispose(swiftparse_parser_t);
 
+/// Set the language version that should be used to parse the Swift source file.
+SWIFTPARSE_PUBLIC void
+swiftparse_parser_set_language_version(swiftparse_parser_t c_parser,
+                                       const char *version);
+
+/// Set whether bare slash regex literals are enabled.
+SWIFTPARSE_PUBLIC void swiftparse_parser_set_enable_bare_slash_regex_literal(
+    swiftparse_parser_t c_parser, bool enabled);
+
 /// Invoked by the parser when a syntax node is parsed. The client should
 /// return a pointer to associate with that particular node.
 typedef swiftparse_client_node_t

tools/libSwiftSyntaxParser/libSwiftSyntaxParser.cpp

@@ -19,6 +19,7 @@
 #include "swift/AST/Module.h"
 #include "swift/Basic/LangOptions.h"
 #include "swift/Basic/SourceManager.h"
+#include "swift/Basic/Version.h"
 #include "swift/Parse/Parser.h"
 #include "swift/Parse/SyntaxParseActions.h"
 #include "swift/Parse/SyntaxRegexFallbackLexing.h"
@@ -58,6 +59,13 @@ class SynParser {
   swiftparse_node_handler_t NodeHandler = nullptr;
   swiftparse_node_lookup_t NodeLookup = nullptr;
   swiftparse_diagnostic_handler_t DiagHandler = nullptr;
+  /// The language version that should be used to parse the Swift source file.
+  /// If \c None this is the default langauge version specified in LangOptions.h
+  Optional<version::Version> EffectiveLanguageVersion;
+
+  /// Whether bare slash regex literals are enabled.
+  /// If \c None this is the default specified in LangOptions.h
+  Optional<bool> EnableBareSlashRegexLiteral;
 
 public:
   swiftparse_node_handler_t getNodeHandler() const {
@@ -90,6 +98,17 @@ class SynParser {
     Block_release(prevBlk);
   }
 
+  void setLanguageVersion(const char *versionString) {
+    if (auto version = version::Version::parseVersionString(
+            versionString, SourceLoc(), /*Diags=*/nullptr)) {
+      this->EffectiveLanguageVersion = version;
+    }
+  }
+
+  void setEnableBareSlashRegexLiteral(bool EnableBareSlashRegexLiteral) {
+    this->EnableBareSlashRegexLiteral = EnableBareSlashRegexLiteral;
+  }
+
   ~SynParser() {
     setNodeHandler(nullptr);
     setNodeLookup(nullptr);
@@ -493,7 +512,12 @@ swiftparse_client_node_t SynParser::parse(const char *source, size_t len) {
 
   // Always enable bare /.../ regex literal in syntax parser.
   langOpts.EnableExperimentalStringProcessing = true;
-  langOpts.EnableBareSlashRegexLiterals = true;
+  if (EnableBareSlashRegexLiteral && *EnableBareSlashRegexLiteral) {
+    langOpts.EnableBareSlashRegexLiterals = true;
+  }
+  if (EffectiveLanguageVersion) {
+    langOpts.EffectiveLanguageVersion = *EffectiveLanguageVersion;
+  }
 
   auto parseActions =
     std::make_shared<CLibParseActions>(*this, SM, bufID);
@@ -517,6 +541,18 @@ swiftparse_parser_create(void) {
   return new SynParser();
 }
 
+void swiftparse_parser_set_language_version(swiftparse_parser_t c_parser,
+                                            const char *version) {
+  SynParser *parser = static_cast<SynParser *>(c_parser);
+  parser->setLanguageVersion(version);
+}
+
+void swiftparse_parser_set_enable_bare_slash_regex_literal(
+    swiftparse_parser_t c_parser, bool enabled) {
+  SynParser *parser = static_cast<SynParser *>(c_parser);
+  parser->setEnableBareSlashRegexLiteral(enabled);
+}
+
 void
 swiftparse_parser_dispose(swiftparse_parser_t c_parser) {
   SynParser *parser = static_cast<SynParser*>(c_parser);

tools/libSwiftSyntaxParser/libSwiftSyntaxParser.exports

@@ -1,5 +1,7 @@
 swiftparse_parse_string
 swiftparse_parser_create
+swiftparse_parser_set_language_version
+swiftparse_parser_set_enable_bare_slash_regex_literal
 swiftparse_parser_dispose
 swiftparse_parser_set_node_handler
 swiftparse_parser_set_node_lookup