Update MD009/no-trailing-spaces to include strict mode (fixes #216).

doc/Rules.md

@@ -318,7 +318,7 @@ Tags: whitespace
 
 Aliases: no-trailing-spaces
 
-Parameters: br_spaces, list_item_empty_lines (number; default 2, boolean; default false)
+Parameters: br_spaces, list_item_empty_lines, strict (number; default 2, boolean; default false, boolean; default false)
 
 This rule is triggered on any lines that end with unexpected whitespace. To fix this,
 remove the trailing space from the end of the line.
@@ -330,9 +330,18 @@ value allows 2 spaces to indicate a hard break (\<br> element).
 Note: You must set `br_spaces` to a value >= 2 for this parameter to take effect.
 Setting `br_spaces` to 1 behaves the same as 0, disallowing any trailing spaces.
 
+By default, this rule will not trigger when the allowed number of spaces is used,
+even when it doesn't create a hard break (for example, at the end of a paragraph).
+To report such instances as well, set the `strict` parameter to `true`.
+
+```markdown
+Text text text
+text[2 spaces]
+```
+
 Using spaces to indent blank lines inside a list item is usually not necessary,
 but some parsers require it. Set the `list_item_empty_lines` parameter to `true`
-to allow this:
+to allow this (even when `strict` is `true`):
 
 ```markdown
 - list item text

lib/md009.js

@@ -2,10 +2,14 @@
 
 "use strict";
 
-const { addError, filterTokens, forEachLine, includesSorted } =
+const { addError, filterTokens, forEachInlineCodeSpan, forEachLine,
-  require("../helpers");
+  includesSorted, newLineRe } = require("../helpers");
 const { lineMetadata } = require("./cache");
 
+function numericSortAscending(a, b) {
+  return a - b;
+}
+
 module.exports = {
   "names": [ "MD009", "no-trailing-spaces" ],
   "description": "Trailing spaces",
@@ -15,17 +19,38 @@ module.exports = {
     if (brSpaces === undefined) {
       brSpaces = 2;
     }
-    const listItemEmptyLines = params.config.list_item_empty_lines;
+    const listItemEmptyLines = !!params.config.list_item_empty_lines;
-    const allowListItemEmptyLines =
+    const strict = !!params.config.strict;
-      (listItemEmptyLines === undefined) ? false : !!listItemEmptyLines;
     const listItemLineNumbers = [];
-    if (allowListItemEmptyLines) {
+    if (listItemEmptyLines) {
       filterTokens(params, "list_item_open", (token) => {
         for (let i = token.map[0]; i < token.map[1]; i++) {
           listItemLineNumbers.push(i + 1);
         }
       });
-      listItemLineNumbers.sort((a, b) => a - b);
+      listItemLineNumbers.sort(numericSortAscending);
+    }
+    const paragraphLineNumbers = [];
+    const codeInlineLineNumbers = [];
+    if (strict) {
+      filterTokens(params, "paragraph_open", (token) => {
+        for (let i = token.map[0]; i < token.map[1] - 1; i++) {
+          paragraphLineNumbers.push(i + 1);
+        }
+      });
+      paragraphLineNumbers.sort(numericSortAscending);
+      filterTokens(params, "inline", (token) => {
+        if (token.children.some((child) => child.type === "code_inline")) {
+          const tokenLines = params.lines.slice(token.map[0], token.map[1]);
+          forEachInlineCodeSpan(tokenLines.join("\n"), (code, lineIndex) => {
+            const codeLineCount = code.split(newLineRe).length;
+            for (let i = 0; i < codeLineCount; i++) {
+              codeInlineLineNumbers.push(token.lineNumber + lineIndex + i);
+            }
+          });
+        }
+      });
+      codeInlineLineNumbers.sort(numericSortAscending);
     }
     const expected = (brSpaces < 2) ? 0 : brSpaces;
     let inFencedCode = 0;
@@ -35,7 +60,10 @@ module.exports = {
       const trailingSpaces = line.length - line.trimRight().length;
       if ((!inCode || inFencedCode) && trailingSpaces &&
         !includesSorted(listItemLineNumbers, lineNumber)) {
-        if (expected !== trailingSpaces) {
+        if ((expected !== trailingSpaces) ||
+            (strict &&
+             (!includesSorted(paragraphLineNumbers, lineNumber) ||
+              includesSorted(codeInlineLineNumbers, lineNumber)))) {
           const column = line.length - trailingSpaces + 1;
           addError(
             onError,

lib/md036.js

@@ -15,7 +15,6 @@ module.exports = {
       if (token.type === "paragraph_open") {
         return function inParagraph(t) {
           // Always paragraph_open/inline/paragraph_close,
-          // omit (t.type === "inline")
           const children = t.children.filter(function notEmptyText(child) {
             return (child.type !== "text") || (child.content !== "");
           });

schema/build-config-schema.js

@@ -109,6 +109,11 @@ rules.forEach(function forRule(rule) {
           "description": "Allow spaces for empty lines in list items",
           "type": "boolean",
           "default": false
+        },
+        "strict": {
+          "description": "Include unnecessary breaks",
+          "type": "boolean",
+          "default": false
         }
       };
       break;

schema/markdownlint-config-schema.json

@@ -267,6 +267,11 @@
           "description": "Allow spaces for empty lines in list items",
           "type": "boolean",
           "default": false
+        },
+        "strict": {
+          "description": "Include unnecessary breaks",
+          "type": "boolean",
+          "default": false
         }
       },
       "additionalProperties": false
@@ -288,6 +293,11 @@
           "description": "Allow spaces for empty lines in list items",
           "type": "boolean",
           "default": false
+        },
+        "strict": {
+          "description": "Include unnecessary breaks",
+          "type": "boolean",
+          "default": false
         }
       },
       "additionalProperties": false

test/hard-line-breaks.json

@@ -0,0 +1,6 @@
+{
+    "default": true,
+    "MD009": {
+      "strict": true
+    }
+  }

test/hard-line-breaks.md

@@ -0,0 +1,64 @@
+# Hard Line Breaks
+
+hard  
+break
+
+hard\
+break
+
+hard    
+break
+
+hard  
+  break
+
+hard\
+  break
+
+*hard  
+break*
+
+*hard\
+break*
+
+`code  
+span`
+
+`code\
+span`
+
+not\
+
+not  
+
+## not\
+
+### not  
+
+- Item
+  
+- Item
+  
+  - Item
+    
+  - Item
+
+Text text
+text `code
+span code  
+span` text
+text
+
+Text text
+text text
+text  
+
+{MD009:9}
+{MD009:24}
+{MD009:32}
+{MD009:36}
+{MD009:39}
+{MD009:41}
+{MD009:43}
+{MD009:48}
+{MD009:54}

test/markdownlint-test.js

@@ -1553,6 +1553,7 @@ module.exports.doc = function doc(test) {
               ruleUsesParams = ruleUsesParams.map(function forUse(use) {
                 return use.split(".").pop();
               });
+              ruleUsesParams.sort();
             }
           } else if (/^Tags: /.test(token.content) && rule) {
             test.deepEqual(token.content.split(tagAliasParameterRe).slice(1),
@@ -1571,6 +1572,7 @@ module.exports.doc = function doc(test) {
                 inDetails = inDetails || (part[0] === "(");
                 return !inDetails;
               });
+            parameters.sort();
             test.deepEqual(parameters, ruleUsesParams,
               "Missing parameter for rule " + rule.names);
             ruleUsesParams = null;

test/trailing-spaces-in-lists-allowed-strict.json

@@ -0,0 +1,7 @@
+{
+  "default": true,
+  "MD009": {
+    "list_item_empty_lines": true,
+    "strict": true
+  }
+}

test/trailing-spaces-in-lists-allowed-strict.md

@@ -0,0 +1,52 @@
+# Heading
+
+1. text
+   text
+1. text
+
+   text
+1. text
+   
+   text
+1. text
+   text
+
+1. text
+   text
+   
+1. text
+   
+{MD009:16}
+{MD009:18}
+
+1. text
+   text
+   1. text
+
+      text
+   1. text
+      
+      text
+   1. text
+      text
+
+   1. text
+      text
+      
+   1. text
+      
+1. text
+   - text
+
+     text
+   - text
+     
+     text
+   - text
+     text
+
+   - text
+     text
+     
+{MD009:37}
+{MD009:50}