feat: implement autofix for md029

Add support for auto-fixing MD029 violations.

Close #949

doc/Rules.md

@@ -1046,6 +1046,8 @@ Parameters:
 - `style`: List style (`string`, default `one_or_ordered`, values `one` /
   `one_or_ordered` / `ordered` / `zero`)
 
+Fixable: Some violations can be fixed by tooling
+
 This rule is triggered for ordered lists that do not either start with '1.' or
 do not have a prefix that increases in numerical order (depending on the
 configured style). The less-common pattern of using '0.' as a first prefix or

doc/md029.md

@@ -9,6 +9,8 @@ Parameters:
 - `style`: List style (`string`, default `one_or_ordered`, values `one` /
   `one_or_ordered` / `ordered` / `zero`)
 
+Fixable: Some violations can be fixed by tooling
+
 This rule is triggered for ordered lists that do not either start with '1.' or
 do not have a prefix that increases in numerical order (depending on the
 configured style). The less-common pattern of using '0.' as a first prefix or

lib/constants.mjs

@@ -4,10 +4,10 @@ export const deprecatedRuleNames = [];
 export const fixableRuleNames = [
   "MD004", "MD005", "MD007", "MD009", "MD010", "MD011",
   "MD012", "MD014", "MD018", "MD019", "MD020", "MD021",
-  "MD022", "MD023", "MD026", "MD027", "MD030", "MD031",
+  "MD022", "MD023", "MD026", "MD027", "MD029", "MD030",
-  "MD032", "MD034", "MD037", "MD038", "MD039", "MD044",
+  "MD031", "MD032", "MD034", "MD037", "MD038", "MD039",
-  "MD047", "MD049", "MD050", "MD051", "MD053", "MD054",
+  "MD044", "MD047", "MD049", "MD050", "MD051", "MD053",
-  "MD058"
+  "MD054", "MD058"
 ];
 export const homepage = "https://github.com/DavidAnson/markdownlint";
 export const version = "0.38.0";

lib/md029.mjs

@@ -14,10 +14,14 @@ const listStyleExamples = {
  * Gets the value of an ordered list item prefix token.
  *
  * @param {import("markdownlint").MicromarkToken} listItemPrefix List item prefix token.
- * @returns {number} List item value.
+ * @returns {{column: number, value: number}} List item column, and value.
  */
 function getOrderedListItemValue(listItemPrefix) {
-  return Number(getDescendantsByType(listItemPrefix, [ "listItemValue" ])[0].text);
+  const listItemValue = getDescendantsByType(listItemPrefix, [ "listItemValue" ])[0];
+  return {
+    "column": listItemValue.startColumn,
+    "value": Number(listItemValue.text)
+  };
 }
 
 /** @type {import("markdownlint").Rule} */
@@ -34,11 +38,11 @@ export default {
       let incrementing = false;
       // Check for incrementing number pattern 1/2/3 or 0/1/2
       if (listItemPrefixes.length >= 2) {
-        const firstValue = getOrderedListItemValue(listItemPrefixes[0]);
+        const first = getOrderedListItemValue(listItemPrefixes[0]);
-        const secondValue = getOrderedListItemValue(listItemPrefixes[1]);
+        const second = getOrderedListItemValue(listItemPrefixes[1]);
-        if ((secondValue !== 1) || (firstValue === 0)) {
+        if ((second.value !== 1) || (first.value === 0)) {
           incrementing = true;
-          if (firstValue === 0) {
+          if (first.value === 0) {
             expected = 0;
           }
         }
@@ -54,7 +58,13 @@ export default {
       }
       // Validate each list item marker
       for (const listItemPrefix of listItemPrefixes) {
-        const actual = getOrderedListItemValue(listItemPrefix);
+        const orderedListItemValue = getOrderedListItemValue(listItemPrefix);
+        const actual = orderedListItemValue.value;
+        const fixInfo = {
+          "editColumn": orderedListItemValue.column,
+          "deleteCount": orderedListItemValue.value.toString().length,
+          "insertText": expected.toString()
+        };
         addErrorDetailIf(
           onError,
           listItemPrefix.startLine,
@@ -62,7 +72,8 @@ export default {
           actual,
           "Style: " + listStyleExamples[listStyle],
           undefined,
-          [ listItemPrefix.startColumn, listItemPrefix.endColumn - listItemPrefix.startColumn ]
+          [ listItemPrefix.startColumn, listItemPrefix.endColumn - listItemPrefix.startColumn ],
+          fixInfo
         );
         if (listStyle === "ordered") {
           expected++;

test/markdownlint-test.mjs

@@ -912,7 +912,7 @@ test("readme", async(t) => {
 });
 
 test("validateJsonUsingConfigSchemaStrict", async(t) => {
-  t.plan(209);
+  t.plan(211);
   // @ts-ignore
   const ajv = new Ajv(ajvOptions);
   const validateSchemaStrict = ajv.compile(configSchemaStrict);

test/ordered-list-item-prefix-double-digits-ordered.md

@@ -0,0 +1,42 @@
+# Ordered list examples
+
+Good list:
+
+1. Item
+2. Item
+3. Item
+4. Item
+5. Item
+6. Item
+7. Item
+8. Item
+9. Item
+10. Item
+11. Item
+
+Bad list 1:
+
+1. Item
+10. Item {MD029}
+9. Item {MD029}
+
+Bad list 2:
+
+11. Item {MD029}
+10. Item {MD029}
+
+Bad list 3
+
+12. Item {MD029}
+1. Item {MD029}
+
+Bad list 4:
+
+0. Item
+10. Item {MD029}
+
+<!-- markdownlint-configure-file {
+  "ol-prefix": {
+    "style": "ordered"
+  }
+} -->

test/ordered-list-item-prefix-sublists-ordered.md

@@ -0,0 +1,47 @@
+# Ordered list examples
+
+Good list and sublist:
+
+1. Item
+2. Item
+    1. Item
+    2. Item
+3. Item
+
+Good list and bad sublist:
+
+1. Item
+2. Item
+    3. Item
+    4. Item
+3. Item
+
+Bad list and good sublist:
+
+1. Item
+4. Item {MD029}
+    1. Item
+    2. Item
+5. Item {MD029}
+
+Bad list and bad sublist:
+
+1. Item
+4. Item {MD029}
+    1. Item
+    3. Item {MD029}
+5. Item {MD029}
+
+Bad list and bad sublist (0):
+
+0. Item
+4. Item {MD029}
+    1. Item
+    3. Item {MD029}
+5. Item {MD029}
+
+<!-- markdownlint-configure-file {
+  "ol-prefix": {
+    "style": "ordered"
+  }
+} -->