enhance

Author: LytixDev

include/interpreter/parser.h

@@ -25,8 +25,13 @@
 
 
 /* types */
+/*
+ * NOTE: I have not categorized the other errors as we never use that information.
+ * TODO: One possible optimization is to store the error msg for each error type in a static table
+ */
 typedef enum {
     PET_EXPECTED_RBRACE,
+    PET_CUSTOME,
 } ParseErrorType;
 
 typedef struct parse_error_t ParseError;

src/interactive/prompt.c

@@ -176,10 +176,10 @@ void prompt_run(Prompt *prompt, bool continuation)
 	    handle_arrow(prompt);
 	    break;
 
-        case KEY_TAB:
-            for (size_t i = 0; i < 4; i++)
-                prompt_buf_insert_at_cursor(prompt, ' ');
-            break;
+	case KEY_TAB:
+	    for (size_t i = 0; i < 4; i++)
+		prompt_buf_insert_at_cursor(prompt, ' ');
+	    break;
 
 	default:
 	    if (PROMPT_ABS_POS(prompt) == prompt->buf_len)

src/interpreter/error.c

@@ -130,13 +130,14 @@ void report_parse_err(ParseError *error, char *full_input)
     REPORT_IMPL("%s[line %zu]%s: Error during parsing: %s\n", ANSI_BOLD_START,
 		error->failed->line + 1, ANSI_BOLD_END, error->msg);
 
-    char *line = offending_line(full_input, error->failed->line);
+    Token *failed = error->failed;
+    char *line = offending_line(full_input, failed->line);
     if (line == NULL) {
 	REPORT_IMPL("Internal error: could not find line where parse error occured");
 	return;
     }
 
-    ErrBuf bf = offending_line_from_offset(line, error->failed->start);
-    err_buf_print(bf, error->failed->end - error->failed->start);
+    ErrBuf bf = offending_line_from_offset(line, failed->start);
+    err_buf_print(bf, error->failed->end - failed->start);
     free(bf.alloced_buffer);
 }

src/interpreter/parser.c

@@ -76,12 +76,12 @@ static Expr *grouping(Parser *parser);
 static Expr *func_def(Parser *parser);
 static ArenaLL arguments(Parser *parser);
 
-static void handle_parse_err(Parser *parser, char *msg);
+static void handle_parse_err(Parser *parser, char *msg, ParseErrorType pet);
 
-static ParseError *new_parse_error(Arena *arena, char *msg, Token *failed)
+static ParseError *new_parse_error(Arena *arena, char *msg, Token *failed, ParseErrorType pet)
 {
     ParseError *error = m_arena_alloc_struct(arena, ParseError);
-    error->err_type = PET_EXPECTED_RBRACE;
+    error->err_type = pet;
     size_t msg_len = strlen(msg); // TODO: could we avoid strlen somehow?
     char *msg_arena = m_arena_alloc(arena, msg_len + 1);
     memcpy(msg_arena, msg, msg_len + 1);
@@ -121,7 +121,7 @@ static Token *advance(Parser *parser)
 static void backup(Parser *parser)
 {
     if (parser->token_pos == 0)
-	handle_parse_err(parser, "Internal error: attempted to backup() at pos = 0");
+	handle_parse_err(parser, "Internal error: attempted to backup() at pos = 0", PET_CUSTOME);
     parser->token_pos--;
 }
 
@@ -163,7 +163,7 @@ static bool check_either(Parser *parser, int step, unsigned int n, ...)
 static Token *consume(Parser *parser, TokenType expected, char *err_msg)
 {
     if (!check_single(parser, expected, 0)) {
-	handle_parse_err(parser, err_msg);
+	handle_parse_err(parser, err_msg, expected == t_rbrace ? PET_EXPECTED_RBRACE : PET_CUSTOME);
 	/* we need to "unconsume" the token before we later advance again */
 	backup(parser);
     }
@@ -208,20 +208,24 @@ static bool match_either(Parser *parser, unsigned int n, ...)
 #define match(parser, ...) match_either(parser, VA_NUMBER_OF_ARGS(__VA_ARGS__), __VA_ARGS__)
 
 
-static void handle_parse_err(Parser *parser, char *msg)
+static void handle_parse_err(Parser *parser, char *msg, ParseErrorType pet)
 {
     parser->n_errors++;
     Token *failed = arraylist_get(parser->tokens, parser->token_pos);
-    ParseError *error = new_parse_error(parser->ast_arena, msg, failed);
-    if (parser->perr_head == NULL) {
+    /*
+     * Edge case where we failed on a newline or the eof.
+     * This ensures the error reporting system is not tripped up because the character
+     * is not found on the expected line.
+     */
+    if ((failed->type == t_eof || failed->type == t_newline) && parser->token_pos != 0)
+	failed = arraylist_get(parser->tokens, parser->token_pos - 1);
+
+    ParseError *error = new_parse_error(parser->ast_arena, msg, failed, pet);
+    if (parser->perr_head == NULL)
 	parser->perr_head = error;
-	parser->perr_tail = error;
-    } else {
+    else
 	parser->perr_tail->next = error;
-	parser->perr_tail = error;
-    }
-
-    // report_parse_err(parser, msg);
+    parser->perr_tail = error;
 
     if (parser->n_errors >= MAX_PARSE_ERRORS) {
 	REPORT_IMPL("TOO MANY PARSE ERRORS. Quitting now ...\n");
@@ -690,7 +694,7 @@ static Expr *single(Parser *parser)
 	CastExpr *expr = (CastExpr *)expr_alloc(parser->ast_arena, EXPR_CAST, parser->source_line);
 	expr->expr = left;
 	if (!match(parser, t_ident)) {
-	    handle_parse_err(parser, "Expected identifier after cast");
+	    handle_parse_err(parser, "Expected identifier after cast", PET_CUSTOME);
 	    /* move past token and continue as normal */
 	    parser->token_pos++;
 	    return NULL;
@@ -786,7 +790,7 @@ static Expr *primary(Parser *parser)
 	return func_def(parser);
 
     if (!match(parser, t_dt_str, t_dt_text_lit)) {
-	handle_parse_err(parser, "Not a valid primary type");
+	handle_parse_err(parser, "Not a valid primary type", PET_CUSTOME);
 	return NULL;
     }
 

src/main.c

@@ -59,16 +59,11 @@ void interactive(int argc, char **argv)
 	    interpreter_run(&interpreter, &parse_result.stmts);
 	} else if ((parse_result.n_errors == 1 || inside_block) &&
 		   parse_result.perr_tail->err_type == PET_EXPECTED_RBRACE) {
-            /* */
+	    /* Change the PS1 to signify we are inside a block */
 	    prompt_set_ps1(&prompt, ".. ");
 	    inside_block = true;
 	    prompt.buf[--prompt.buf_len] = 0; /* Pop EOF. We are continuing. */
-
-	    arraylist_free(&lex_result.tokens);
-	    arraylist_free(&parse_result.stmts);
-	    m_arena_clear(&ast_arena);
-
-	    continue;
+	    goto continue_repl;
 	} else {
 	    report_all_parse_errors(parse_result.perr_head, prompt.buf);
 	}
@@ -78,7 +73,7 @@ void interactive(int argc, char **argv)
 	    inside_block = false;
 	}
 
-	// TODO: these should maybe be reset (e.i. set size to 0), not freed
+continue_repl:
 	arraylist_free(&lex_result.tokens);
 	arraylist_free(&parse_result.stmts);
 	m_arena_clear(&ast_arena);
@@ -89,7 +84,6 @@ void interactive(int argc, char **argv)
     prompt_free(&prompt);
 }
 
-
 int main(int argc, char **argv)
 {
     if (argc == 1) {