feat(parser): starting to believe in lists

src/_include/mrk/parser_internal.h

@@ -50,6 +50,12 @@ mrk_err mrk_parser_eat(mrk_token *out, mrk_parser *parser, mrk_token_type type);
  */
 void mrk_parser_indent(mrk_parser *parser);
 
+/**
+ * Parse all elements on the parser's current indentation level. If the level is
+ * 0, this will parse the entire file.
+ */
+mrk_err mrk_parser_parse_indent_block(mrk_parser *parser, mrk_ast_node *parent);
+
 /**
  * Parse an entire header block.
  */
@@ -69,6 +75,13 @@ mrk_err mrk_parser_parse_paragraph(mrk_ast_node *out, mrk_parser *parser);
  */
 mrk_err mrk_parser_parse_text(mrk_ast_node *out, mrk_parser *parser);
 
+/**
+ * Parse any tokens that have the same meaning no matter the context and append
+ * them to the parent. This includes text tokens and links. Only tokens within
+ * the same indentation level are matched.
+ */
+mrk_err mrk_parser_parse_common(mrk_parser *parser, mrk_ast_node *parent);
+
 /**
  * Parse a link construct
  */
@@ -79,4 +92,6 @@ mrk_err mrk_parser_parse_link(mrk_ast_node *out, mrk_parser *parser);
  */
 mrk_err mrk_parser_parse_list(mrk_ast_node *out, mrk_parser *parser);
 
+mrk_err mrk_parser_parse_list_item(mrk_ast_node *out, mrk_parser *parser);
+
 #endif

src/parser/parser.c

@@ -17,12 +17,24 @@ void mrk_parser_open(mrk_parser *parser, mrk_lexer *lexer) {
 mrk_err mrk_parser_parse(mrk_ast_node **out, mrk_parser *parser) {
   mrk_ast_node *root;
   MRK_RES(mrk_ast_node_init(&root));
+  mrk_parser_indent(parser);
 
   while (!mrk_parser_done(parser)) {
-    mrk_parser_indent(parser);
+    MRK_RES(mrk_parser_parse_indent_block(parser, root));
+  }
 
+  *out = root;
+
+  return mrk_err_ok;
+}
+
+mrk_err mrk_parser_parse_indent_block(mrk_parser *parser,
+                                      mrk_ast_node *parent) {
+  size_t indent = parser->indent;
+
+  while (!mrk_parser_done(parser) && parser->indent == indent) {
     mrk_ast_node *child;
-    MRK_RES(mrk_ast_node_child_append(&child, root));
+    MRK_RES(mrk_ast_node_child_append(&child, parent));
 
     switch (mrk_parser_peek(parser).type) {
     case mrk_token_type_header_start:
@@ -32,11 +44,15 @@ mrk_err mrk_parser_parse(mrk_ast_node **out, mrk_parser *parser) {
     case mrk_token_type_left_bracket:
       MRK_RES(mrk_parser_parse_paragraph(child, parser));
       break;
+    case mrk_token_type_list_item_unordered:
+    case mrk_token_type_list_item_checked:
+    case mrk_token_type_list_item_unchecked:
+    case mrk_token_type_list_item_ordered:
+      MRK_RES(mrk_parser_parse_list(child, parser));
+      break;
     }
   }
 
-  *out = root;
-
   return mrk_err_ok;
 }
 
@@ -47,35 +63,11 @@ mrk_err mrk_parser_parse_header(mrk_ast_node *out, mrk_parser *parser) {
   out->type = mrk_ast_node_type_header;
   out->d.header.depth = mrk_token_len(header_token);
 
-  size_t header_indent = parser->indent;
+  // All continuation lines of the header should be one indentation deeper than
+  // the definition of the header
+  parser->indent++;
 
-  // Parse subsections of header
+  MRK_RES(mrk_parser_parse_common(parser, out));
-  while (!mrk_parser_done(parser) && parser->indent == header_indent) {
-    mrk_ast_node *child;
-
-    switch (mrk_parser_peek(parser).type) {
-    case mrk_token_type_text:
-      MRK_RES(mrk_ast_node_child_append(&child, out));
-      MRK_RES(mrk_parser_parse_text(child, parser));
-      break;
-    // Newlines are interpreted as spaces
-    case mrk_token_type_newline:
-      MRK_RES(mrk_ast_node_child_append(&child, out));
-      child->type = mrk_ast_node_type_space;
-      mrk_parser_advance(parser);
-      mrk_parser_indent(parser);
-      break;
-    case mrk_token_type_left_bracket:
-      MRK_RES(mrk_ast_node_child_append(&child, out));
-      MRK_RES(mrk_parser_parse_link(child, parser));
-      break;
-    // Header definition ends at newline
-    case mrk_token_type_blank_line:
-      mrk_parser_advance(parser);
-      mrk_parser_indent(parser);
-      return mrk_err_ok;
-    }
-  }
 
   return mrk_err_ok;
 }
@@ -91,6 +83,40 @@ mrk_err mrk_parser_parse_text(mrk_ast_node *out, mrk_parser *parser) {
   return mrk_err_ok;
 }
 
+mrk_err mrk_parser_parse_common(mrk_parser *parser, mrk_ast_node *parent) {
+  size_t indent = parser->indent;
+
+  while (!mrk_parser_done(parser) && parser->indent == indent) {
+    mrk_ast_node *child;
+
+    switch (mrk_parser_peek(parser).type) {
+    case mrk_token_type_text:
+      MRK_RES(mrk_ast_node_child_append(&child, parent));
+      MRK_RES(mrk_parser_parse_text(child, parser));
+      break;
+    case mrk_token_type_left_bracket:
+      MRK_RES(mrk_ast_node_child_append(&child, parent));
+      MRK_RES(mrk_parser_parse_link(child, parser));
+      break;
+    case mrk_token_type_newline:
+      MRK_RES(mrk_ast_node_child_append(&child, parent));
+      child->type = mrk_ast_node_type_space;
+      mrk_parser_advance(parser);
+      mrk_parser_indent(parser);
+      break;
+    case mrk_token_type_blank_line:
+      mrk_parser_advance(parser);
+      mrk_parser_indent(parser);
+      return mrk_err_ok;
+    // Any other tokens aren't part of the common section so we just exit
+    default:
+      return mrk_err_ok;
+    }
+  }
+
+  return mrk_err_ok;
+}
+
 mrk_err mrk_parser_parse_link(mrk_ast_node *out, mrk_parser *parser) {
   out->type = mrk_ast_node_type_link;
 
@@ -132,29 +158,56 @@ mrk_err mrk_parser_parse_link(mrk_ast_node *out, mrk_parser *parser) {
 mrk_err mrk_parser_parse_paragraph(mrk_ast_node *out, mrk_parser *parser) {
   out->type = mrk_ast_node_type_paragraph;
 
+  MRK_RES(mrk_parser_parse_common(parser, out));
+
+  return mrk_err_ok;
+}
+
+mrk_err mrk_parser_parse_list(mrk_ast_node *out, mrk_parser *parser) {
+  out->type = mrk_ast_node_type_list;
+
   size_t indent = parser->indent;
 
-  while (!mrk_parser_done(parser) && parser->indent == indent) {
+  switch (mrk_parser_peek(parser).type) {
-    mrk_ast_node *child;
+  case mrk_token_type_list_item_unordered:
+  case mrk_token_type_list_item_checked:
+  case mrk_token_type_list_item_unchecked:
+    out->d.list.ordered = false;
+    break;
+  case mrk_token_type_list_item_ordered:
+    out->d.list.ordered = true;
+    break;
+    // TODO error on default
+  }
 
+  mrk_ast_node *child;
+  MRK_RES(mrk_ast_node_child_append(&child, out));
+  MRK_RES(mrk_parser_parse_list_item(child, parser));
+
+  while (!mrk_parser_done(parser) && parser->indent == indent) {
     switch (mrk_parser_peek(parser).type) {
-    case mrk_token_type_text:
+    case mrk_token_type_list_item_unordered:
+    case mrk_token_type_list_item_checked:
+    case mrk_token_type_list_item_unchecked:
+      // Two lists of different types can follow up on each other
+      if (out->d.list.ordered) {
+        return mrk_err_ok;
+      }
+
       MRK_RES(mrk_ast_node_child_append(&child, out));
-      MRK_RES(mrk_parser_parse_text(child, parser));
+      MRK_RES(mrk_parser_parse_list_item(child, parser));
       break;
-    case mrk_token_type_left_bracket:
+    case mrk_token_type_list_item_ordered:
+      // Two lists of different types can follow up on each other
+      if (!out->d.list.ordered) {
+        return mrk_err_ok;
+      }
+
       MRK_RES(mrk_ast_node_child_append(&child, out));
-      MRK_RES(mrk_parser_parse_link(child, parser));
+      MRK_RES(mrk_parser_parse_list_item(child, parser));
       break;
-    case mrk_token_type_newline:
+    // Other tokens imply end of list
-      MRK_RES(mrk_ast_node_child_append(&child, out));
+    default:
-      child->type = mrk_ast_node_type_space;
-      mrk_parser_advance(parser);
-      mrk_parser_indent(parser);
-      break;
-    case mrk_token_type_blank_line:
-      mrk_parser_advance(parser);
-      mrk_parser_indent(parser);
       return mrk_err_ok;
     }
   }
@@ -162,6 +215,39 @@ mrk_err mrk_parser_parse_paragraph(mrk_ast_node *out, mrk_parser *parser) {
   return mrk_err_ok;
 }
 
-mrk_err mrk_parser_parse_list(mrk_ast_node *out, mrk_parser *parser) {
+mrk_err mrk_parser_parse_list_item(mrk_ast_node *out, mrk_parser *parser) {
-  return mrk_err_invalid;
+  out->type = mrk_ast_node_type_list_item;
+
+  size_t indent = parser->indent;
+
+  switch (mrk_parser_peek(parser).type) {
+  case mrk_token_type_list_item_unordered:
+  case mrk_token_type_list_item_ordered:
+    out->d.list_item.checkbox = false;
+    out->d.list_item.checked = false;
+    break;
+  case mrk_token_type_list_item_checked:
+    out->d.list_item.checkbox = true;
+    out->d.list_item.checked = true;
+    break;
+  case mrk_token_type_list_item_unchecked:
+    out->d.list_item.checkbox = true;
+    out->d.list_item.checked = false;
+    break;
+  // This path should never be taken
+  default:;
+  }
+
+  mrk_parser_advance(parser);
+
+  // Parse the textual part of the list
+  parser->indent++;
+  MRK_RES(mrk_parser_parse_common(parser, out));
+
+  // This allows lists to be arbitrarily nested
+  if (!mrk_parser_done(parser) && parser->indent > indent) {
+    MRK_RES(mrk_parser_parse_indent_block(parser, out));
+  }
+
+  return mrk_err_ok;
 }

test/parser/specific.c

@@ -58,7 +58,7 @@ void test_parse_link() {
 }
 
 void test_parse_unordered_list() {
-  const char *buf = "* element one\n* element two\n    paragraph in element two";
+  const char *buf = "* element one\n* element two\n\n    paragraph in element two";
   PARSER_OPEN(buf);
 
   mrk_ast_node *list;
@@ -94,8 +94,8 @@ void test_parse_unordered_list() {
   TEST_CHECK(subchild->children.len == 1);
 
   TEST_CHECK(subchild->children.arr[0]->type == mrk_ast_node_type_text);
-  TEST_CHECK(subchild->children.arr[0]->d.text.start == 31);
+  TEST_CHECK(subchild->children.arr[0]->d.text.start == 33);
-  TEST_CHECK(subchild->children.arr[0]->d.text.end == 55);
+  TEST_CHECK(subchild->children.arr[0]->d.text.end == 57);
 }
 
 TEST_LIST = {