Add support for controlling the start of a marker

Closes GH-4.
Closes GH-6.

index.js

@@ -82,27 +82,27 @@ function messageControl(options) {
       length = ruleIds.length
       index = -1
 
-      while (++index < length) {
-        ruleId = ruleIds[index]
-
-        if (isKnown(ruleId, verb, mark.node)) {
-          toggle(pos, verb === 'enable', ruleId)
-
-          if (verb === 'ignore') {
-            toggle(tail, true, ruleId)
-          }
-        }
-      }
-
       // Apply to all rules.
-      if (!length) {
+      if (length === 0) {
         if (verb === 'ignore') {
           toggle(pos, false)
           toggle(tail, true)
         } else {
           toggle(pos, verb === 'enable')
           reset = verb !== 'enable'
         }
+      } else {
+        while (++index < length) {
+          ruleId = ruleIds[index]
+
+          if (isKnown(ruleId, verb, mark.node)) {
+            toggle(pos, verb === 'enable', ruleId)
+
+            if (verb === 'ignore') {
+              toggle(tail, true, ruleId)
+            }
+          }
+        }
       }
     }
 
@@ -177,7 +177,6 @@ function messageControl(options) {
     // Handle a rule.
     function toggle(pos, state, ruleId) {
       var markers = ruleId ? scope[ruleId] : globals
-      var currentState
       var previousState
 
       if (!markers) {
@@ -186,10 +185,9 @@ function messageControl(options) {
       }
 
       previousState = getState(ruleId)
-      currentState = state
 
-      if (currentState !== previousState) {
-        markers.push({state: currentState, position: pos})
+      if (state !== previousState) {
+        markers.push({state: state, position: pos})
       }
 
       // Toggle all known rules.
@@ -218,7 +216,7 @@ function messageControl(options) {
         if (
           range.position.line < message.line ||
           (range.position.line === message.line &&
-            range.position.column < message.column)
+            range.position.column <= message.column)
         ) {
           return range.state === true
         }

test.js

@@ -647,5 +647,95 @@ test('control()', function(t) {
       )
     })
 
+  remark()
+    .use(function() {
+      var transformer = control({
+        name: 'foo',
+        marker: mdastMarker,
+        test: 'html'
+      })
+
+      return function(tree, file) {
+        file.message('Error', {line: 1, column: 1}, 'foo:bar')
+
+        transformer(tree, file)
+      }
+    })
+    .process('<!--foo disable bar-->\n', function(err, file) {
+      t.deepEqual(
+        [err].concat(file.messages.map(String)),
+        [null],
+        'should disable messages at the start of a marker'
+      )
+    })
+
+  remark()
+    .use(function() {
+      var transformer = control({
+        name: 'foo',
+        marker: mdastMarker,
+        test: 'html',
+        reset: true
+      })
+
+      return function(tree, file) {
+        file.message('Error', {line: 1, column: 1}, 'foo:bar')
+
+        transformer(tree, file)
+      }
+    })
+    .process('<!--foo enable-->\n', function(err, file) {
+      t.deepEqual(
+        [err].concat(file.messages.map(String)),
+        [null, '1:1: Error'],
+        'should enable messages at the start of a marker'
+      )
+    })
+
+  remark()
+    .use(function() {
+      var transformer = control({
+        name: 'foo',
+        marker: mdastMarker,
+        test: 'html'
+      })
+
+      return function(tree, file) {
+        file.message('Error', 'foo:bar')
+
+        transformer(tree, file)
+      }
+    })
+    .process('<!--foo disable bar-->\n', function(err, file) {
+      t.deepEqual(
+        [err].concat(file.messages.map(String)),
+        [null],
+        'should disable messages without positional info (at the start of a document)'
+      )
+    })
+
+  remark()
+    .use(function() {
+      var transformer = control({
+        name: 'foo',
+        marker: mdastMarker,
+        test: 'html',
+        reset: true
+      })
+
+      return function(tree, file) {
+        file.message('Error', 'foo:bar')
+
+        transformer(tree, file)
+      }
+    })
+    .process('<!--foo enable-->\n', function(err, file) {
+      t.deepEqual(
+        [err].concat(file.messages.map(String)),
+        [null, '1:1: Error'],
+        'should enable messages without positional info (at the start of a document)'
+      )
+    })
+
   t.end()
 })