Flatten the scanner

src/scanner.c

@@ -2,18 +2,15 @@
 //
 //
 //
-// Scanners are not extensible, so we have to copy them,
-//
-// To Update:
-//  - delete everything under the comment block
-//  - find and replace "tree_sitter_javascript" with "tree_sitter_glimmer_typescript"
-//    - there should be 5 methods updated
-//    - %s/tree_sitter_javascript/tree_sitter_glimmer_typescript/g
+// Scanners are not extensible, so we have to copy them
 //
+// rename external_scanner_scan => tree_sitter_glimmer_typescript_external_scanner_scan
 //
 //
 // ----------------------------------------------------------
-#include "./tree-sitter-typescript/scanner.h"
+#include "tree_sitter/parser.h"
+
+#include <wctype.h>
 
 void *tree_sitter_glimmer_typescript_external_scanner_create() { return NULL; }
 
@@ -23,6 +20,307 @@ unsigned tree_sitter_glimmer_typescript_external_scanner_serialize(void *payload
 
 void tree_sitter_glimmer_typescript_external_scanner_deserialize(void *payload, const char *buffer, unsigned length) {}
 
+// bool tree_sitter_glimmer_typescript_external_scanner_scan(void *payload, TSLexer *lexer, const bool *valid_symbols) {
+//     return external_scanner_scan(payload, lexer, valid_symbols);
+// }
+
+/***********************************
+ *
+ * from tree-sitter-typescript v0.21.0
+ *
+ * ***********************************/
+enum TokenType {
+    AUTOMATIC_SEMICOLON,
+    TEMPLATE_CHARS,
+    TERNARY_QMARK,
+    HTML_COMMENT,
+    LOGICAL_OR,
+    ESCAPE_SEQUENCE,
+    REGEX_PATTERN,
+    FUNCTION_SIGNATURE_AUTOMATIC_SEMICOLON,
+    ERROR_RECOVERY,
+};
+
+static void advance(TSLexer *lexer) { lexer->advance(lexer, false); }
+
+static void skip(TSLexer *lexer) { lexer->advance(lexer, true); }
+
+static bool scan_template_chars(TSLexer *lexer) {
+    lexer->result_symbol = TEMPLATE_CHARS;
+    for (bool has_content = false;; has_content = true) {
+        lexer->mark_end(lexer);
+        switch (lexer->lookahead) {
+            case '`':
+                return has_content;
+            case '\0':
+                return false;
+            case '$':
+                advance(lexer);
+                if (lexer->lookahead == '{') {
+                    return has_content;
+                }
+                break;
+            case '\\':
+                return has_content;
+            default:
+                advance(lexer);
+        }
+    }
+}
+
+static bool scan_whitespace_and_comments(TSLexer *lexer, bool *scanned_comment) {
+    for (;;) {
+        while (iswspace(lexer->lookahead)) {
+            skip(lexer);
+        }
+
+        if (lexer->lookahead == '/') {
+            skip(lexer);
+
+            if (lexer->lookahead == '/') {
+                skip(lexer);
+                while (lexer->lookahead != 0 && lexer->lookahead != '\n') {
+                    skip(lexer);
+                }
+                *scanned_comment = true;
+            } else if (lexer->lookahead == '*') {
+                skip(lexer);
+                while (lexer->lookahead != 0) {
+                    if (lexer->lookahead == '*') {
+                        skip(lexer);
+                        if (lexer->lookahead == '/') {
+                            skip(lexer);
+                            break;
+                        }
+                    } else {
+                        skip(lexer);
+                    }
+                }
+            } else {
+                return false;
+            }
+        } else {
+            return true;
+        }
+    }
+}
+
+static bool scan_automatic_semicolon(TSLexer *lexer, const bool *valid_symbols, bool *scanned_comment) {
+    lexer->result_symbol = AUTOMATIC_SEMICOLON;
+    lexer->mark_end(lexer);
+
+    for (;;) {
+        if (lexer->lookahead == 0) {
+            return true;
+        }
+        if (lexer->lookahead == '}') {
+            // Automatic semicolon insertion breaks detection of object patterns
+            // in a typed context:
+            //   type F = ({a}: {a: number}) => number;
+            // Therefore, disable automatic semicolons when followed by typing
+            do {
+                skip(lexer);
+            } while (iswspace(lexer->lookahead));
+            if (lexer->lookahead == ':') {
+                return valid_symbols[LOGICAL_OR]; // Don't return false if we're in a ternary by checking if || is valid
+            }
+            return true;
+        }
+        if (!iswspace(lexer->lookahead)) {
+            return false;
+        }
+        if (lexer->lookahead == '\n') {
+            break;
+        }
+        skip(lexer);
+    }
+
+    skip(lexer);
+
+    if (!scan_whitespace_and_comments(lexer, scanned_comment)) {
+        return false;
+    }
+
+    switch (lexer->lookahead) {
+        case ',':
+        case '.':
+        case ';':
+        case '*':
+        case '%':
+        case '>':
+        case '<':
+        case '=':
+        case '?':
+        case '^':
+        case '|':
+        case '&':
+        case '/':
+        case ':':
+            return false;
+
+        case '{':
+            if (valid_symbols[FUNCTION_SIGNATURE_AUTOMATIC_SEMICOLON]) {
+                return false;
+            }
+            break;
+
+            // Don't insert a semicolon before a '[' or '(', unless we're parsing
+            // a type. Detect whether we're parsing a type or an expression using
+            // the validity of a binary operator token.
+        case '(':
+        case '[':
+            if (valid_symbols[LOGICAL_OR]) {
+                return false;
+            }
+            break;
+
+            // Insert a semicolon before `--` and `++`, but not before binary `+` or `-`.
+        case '+':
+            skip(lexer);
+            return lexer->lookahead == '+';
+        case '-':
+            skip(lexer);
+            return lexer->lookahead == '-';
+
+            // Don't insert a semicolon before `!=`, but do insert one before a unary `!`.
+        case '!':
+            skip(lexer);
+            return lexer->lookahead != '=';
+
+            // Don't insert a semicolon before `in` or `instanceof`, but do insert one
+            // before an identifier.
+        case 'i':
+            skip(lexer);
+
+            if (lexer->lookahead != 'n') {
+                return true;
+            }
+            skip(lexer);
+
+            if (!iswalpha(lexer->lookahead)) {
+                return false;
+            }
+
+            for (unsigned i = 0; i < 8; i++) {
+                if (lexer->lookahead != "stanceof"[i]) {
+                    return true;
+                }
+                skip(lexer);
+            }
+
+            if (!iswalpha(lexer->lookahead)) {
+                return false;
+            }
+            break;
+    }
+
+    return true;
+}
+
+static bool scan_ternary_qmark(TSLexer *lexer) {
+    for (;;) {
+        if (!iswspace(lexer->lookahead)) {
+            break;
+        }
+        skip(lexer);
+    }
+
+    if (lexer->lookahead == '?') {
+        advance(lexer);
+
+        /* Optional chaining. */
+        if (lexer->lookahead == '?' || lexer->lookahead == '.') {
+            return false;
+        }
+
+        lexer->mark_end(lexer);
+        lexer->result_symbol = TERNARY_QMARK;
+
+        /* TypeScript optional arguments contain the ?: sequence, possibly
+           with whitespace. */
+        for (;;) {
+            if (!iswspace(lexer->lookahead)) {
+                break;
+            }
+            advance(lexer);
+        }
+
+        if (lexer->lookahead == ':' || lexer->lookahead == ')' || lexer->lookahead == ',') {
+            return false;
+        }
+
+        if (lexer->lookahead == '.') {
+            advance(lexer);
+            if (iswdigit(lexer->lookahead)) {
+                return true;
+            }
+            return false;
+        }
+        return true;
+    }
+    return false;
+}
+
+static bool scan_closing_comment(TSLexer *lexer) {
+    while (iswspace(lexer->lookahead) || lexer->lookahead == 0x2028 || lexer->lookahead == 0x2029) {
+        skip(lexer);
+    }
+
+    const char *comment_start = "<!--";
+    const char *comment_end = "-->";
+
+    if (lexer->lookahead == '<') {
+        for (unsigned i = 0; i < 4; i++) {
+            if (lexer->lookahead != comment_start[i]) {
+                return false;
+            }
+            advance(lexer);
+        }
+    } else if (lexer->lookahead == '-') {
+        for (unsigned i = 0; i < 3; i++) {
+            if (lexer->lookahead != comment_end[i]) {
+                return false;
+            }
+            advance(lexer);
+        }
+    } else {
+        return false;
+    }
+
+    while (lexer->lookahead != 0 && lexer->lookahead != '\n' && lexer->lookahead != 0x2028 &&
+           lexer->lookahead != 0x2029) {
+        advance(lexer);
+    }
+
+    lexer->result_symbol = HTML_COMMENT;
+    lexer->mark_end(lexer);
+
+    return true;
+}
+
 bool tree_sitter_glimmer_typescript_external_scanner_scan(void *payload, TSLexer *lexer, const bool *valid_symbols) {
-    return external_scanner_scan(payload, lexer, valid_symbols);
+    if (valid_symbols[TEMPLATE_CHARS]) {
+        if (valid_symbols[AUTOMATIC_SEMICOLON]) {
+            return false;
+        }
+        return scan_template_chars(lexer);
+    }
+    if (valid_symbols[AUTOMATIC_SEMICOLON] || valid_symbols[FUNCTION_SIGNATURE_AUTOMATIC_SEMICOLON]) {
+        bool scanned_comment = false;
+        bool ret = scan_automatic_semicolon(lexer, valid_symbols, &scanned_comment);
+        if (!ret && !scanned_comment && valid_symbols[TERNARY_QMARK] && lexer->lookahead == '?') {
+            return scan_ternary_qmark(lexer);
+        }
+        return ret;
+    }
+    if (valid_symbols[TERNARY_QMARK]) {
+        return scan_ternary_qmark(lexer);
+    }
+
+    if (valid_symbols[HTML_COMMENT] && !valid_symbols[LOGICAL_OR] && !valid_symbols[ESCAPE_SEQUENCE] &&
+        !valid_symbols[REGEX_PATTERN]) {
+        return scan_closing_comment(lexer);
+    }
+
+    return false;
 }