feat: keep order of preferred selector types when generating selector

src/css-selector-generator.coffee

@@ -2,7 +2,7 @@ class CssSelectorGenerator
 
   default_options:
     # choose from 'tag', 'id', 'class', 'nthchild', 'attribute'
-    selectors: ['tag', 'id', 'class', 'nthchild']
+    selectors: ['id', 'class', 'tag', 'nthchild']
 
   constructor: (options = {}) ->
     @options = {}
@@ -132,64 +132,72 @@ class CssSelectorGenerator
     found_elements.length is 1 and found_elements[0] is element
 
 
-  getUniqueSelector: (element) ->
+  # helper function that tests all combinations for uniqueness
+  testCombinations: (element, items, tag) ->
+    for item in @getCombinations items
+      return item if @testUniqueness element, item
 
-    ###
-    for selector_type in @options.selectors
-      console.log 'selector type', selector_type
-    ###
+    # if tag selector is enabled, try attaching it
+    if tag?
+      for item in (items.map (item) -> tag + item)
+        return item if @testUniqueness element, item
 
+
+  getUniqueSelector: (element) ->
     selectors = @getAllSelectors element
 
-    # ID selector (no need to check for uniqueness)
-    return selectors.i if selectors.i?
+    for selector_type in @options.selectors
 
-    # tag selector (should return unique for BODY)
-    if selectors.t?
-      return selectors.t if @testUniqueness element, selectors.t
+      switch selector_type
 
-    # class selector
-    if selectors.c? and selectors.c.length isnt 0
-      for item in @getCombinations selectors.c
-        return item if @testUniqueness element, item
+        # ID selector (no need to check for uniqueness)
+        when 'id'
+          if selectors.i?
+            return selectors.i
 
-      # if tag selector is enabled, try attaching it
-      if selectors.t?
-        for item in @getCombinations selectors.c, selectors.t
-          return item if @testUniqueness element, item
+        # tag selector (should return unique for BODY)
+        when 'tag'
+          if selectors.t?
+            return selectors.t if @testUniqueness element, selectors.t
 
-    # attribute selector
-    if selectors.a? and selectors.a.length isnt 0
-      for item in @getCombinations selectors.a
-        return item if @testUniqueness element, item
+        # class selector
+        when 'class'
+          if selectors.c? and selectors.c.length isnt 0
+            found_selector = @testCombinations element, selectors.c, selectors.t
+            return found_selector if found_selector
 
-      # if tag selector is enabled, try attaching it
-      if selectors.t?
-        for item in @getCombinations selectors.a, selectors.t
-          return item if @testUniqueness element, item
+        # attribute selector
+        when 'attribute'
+          if selectors.a? and selectors.a.length isnt 0
+            found_selector = @testCombinations element, selectors.a, selectors.t
+            return found_selector if found_selector
 
+        # if anything else fails, return n-th child selector
+        when 'nthchild'
+          if selectors.n?
+            return selectors.n
 
-    # if anything else fails, return n-th child selector
-    return selectors.n
+    return '*'
 
 
   getSelector: (element) ->
     all_selectors = []
+
     parents = @getParents element
     for item in parents
       selector = @getUniqueSelector item
       all_selectors.push selector if selector?
+
     selectors = []
     for item in all_selectors
       selectors.unshift item
       result = selectors.join ' > '
       return result if @testSelector element, result
-    null
-
 
+    return null
 
 
-  getCombinations: (items = [], prefix = '') ->
+  getCombinations: (items = []) ->
     # first item must be empty (seed), it will be removed later
     result = [[]]
 
@@ -204,7 +212,7 @@ class CssSelectorGenerator
     result = result.sort (a, b) -> a.length - b.length
 
     # collapse combinations and add prefix
-    result = result.map (item) -> prefix + item.join ''
+    result = result.map (item) -> item.join ''
 
     result
 

test/src/css-selector-generator.spec.coffee

@@ -86,7 +86,8 @@ describe 'CSS Selector Generator', ->
   describe 'options', ->
 
     it 'should use default set of allowed selectors', ->
-      expect(x.options.selectors).toEqual ['tag', 'id', 'class', 'nthchild']
+      expectation = ['tag', 'id', 'class', 'nthchild']
+      expect(x.options.selectors).toEqual jasmine.arrayContaining expectation
 
     it 'should allow to customize allowed selectors', ->
       x.setOptions selectors: ['attribute']
@@ -97,6 +98,17 @@ describe 'CSS Selector Generator', ->
       x.setOptions selectors: ['tag']
       expect(x.getSelector root.firstChild).toEqual null
 
+    it 'should keep order of prefered selector types', ->
+      root.innerHTML = '<div id="aaa"></div>'
+
+      x.setOptions selectors: ['id', 'tag', 'nthchild']
+      result = (x.getSelector root.firstChild).split(' > ').pop()
+      expect(result).toEqual '#aaa'
+
+      x.setOptions selectors: ['tag', 'id', 'nthchild']
+      result = (x.getSelector root.firstChild).split(' > ').pop()
+      expect(result).toEqual 'div'
+
 
   describe 'selectors', ->
 
@@ -204,7 +216,7 @@ describe 'CSS Selector Generator', ->
         expect(x.getClassSelectors root).toEqual []
 
       it 'should use attribute selector when enabled', ->
-        x.setOptions selectors: ['tag', 'id', 'class', 'nthchild', 'attribute']
+        x.setOptions selectors: ['tag', 'id', 'class', 'attribute', 'nthchild']
         root.innerHTML = '<a rel="aaa"></a><a rel="bbb"></a>'
         result = x.getSelector root.firstChild
         expect(result).toEqual '[rel=aaa]'
@@ -299,22 +311,10 @@ describe 'CSS Selector Generator', ->
 
       it 'should return all possible combinations of items', ->
         result = x.getCombinations ['a', 'b', 'c']
-        expect(result).toContain 'a'
-        expect(result).toContain 'b'
-        expect(result).toContain 'c'
-        expect(result).toContain 'ab'
-        expect(result).toContain 'ac'
-        expect(result).toContain 'bc'
-        expect(result).toContain 'abc'
-        expect(result).not.toContain ''
-        expect(result).not.toContain 'aa'
+        expectation = ['a', 'b', 'c', 'ab', 'ac', 'bc', 'abc']
+        expect(result).toEqual jasmine.arrayContaining expectation
+        expect(result).not.toEqual jasmine.arrayContaining ['', 'aa']
 
       it 'should sort results from shortest to longest', ->
         result = x.getCombinations ['a', 'b', 'c']
-        expect(result[6]).toEqual 'abc'
-
-      it 'should add prefix to combinations', ->
-        result = x.getCombinations ['a', 'b'], 'x'
-        expect(result).toContain 'xa'
-        expect(result).toContain 'xb'
-        expect(result).toContain 'xab'
+        expect(result.pop()).toEqual 'abc'