Page#revise raises ValidationError if a revision is exactly same as the page before

app/models/page.rb

@@ -15,6 +15,11 @@ class Page
   end
 
   def revise(content, created_at, author)
+    if not @revisions.empty? and content == @revisions.last.content
+      raise Instiki::ValidationError.new(
+          "You have tried to save page '#{name}' without changing its content")
+    end
+  
     # A user may change a page, look at it and make some more changes - several times.
     # Not to record every such iteration as a new revision, if the previous revision was done 
     # by the same author, not more than 30 minutes ago, then update the last revision instead of
@@ -81,4 +86,5 @@ class Page
     def method_missing(method_symbol)
       revisions.last.send(method_symbol)
     end
+
 end

test/unit/page_test.rb

@@ -11,6 +11,7 @@ class MockWeb < Web
 end
 
 class PageTest < Test::Unit::TestCase
+
   def setup
     @page = Page.new(
       MockWeb.new,
@@ -21,11 +22,7 @@ class PageTest < Test::Unit::TestCase
     )
   end
 
-  def test_basics
+  def test_lock
-    assert_equal "First Page", @page.plain_name
-  end
-
-  def test_locking
     assert !@page.locked?(Time.local(2004, 4, 4, 16, 50))
 
     @page.lock(Time.local(2004, 4, 4, 16, 30), "DavidHeinemeierHansson")
@@ -38,17 +35,50 @@ class PageTest < Test::Unit::TestCase
     assert !@page.locked?(Time.local(2004, 4, 4, 16, 50))
   end
   
-  def test_locking_duration
+  def test_lock_duration
     @page.lock(Time.local(2004, 4, 4, 16, 30), "DavidHeinemeierHansson")
 
     assert_equal 15, @page.lock_duration(Time.local(2004, 4, 4, 16, 45))
   end
   
-  def test_revision
+  def test_plain_name
-    @page.revise("HisWay would be MyWay in kinda lame", Time.local(2004, 4, 4, 16, 55), "MarianneSyhler")
+    assert_equal "First Page", @page.plain_name
-    assert_equal 2, @page.revisions.length, "Should have two revisions"
+  end
-    assert_equal "MarianneSyhler", @page.author, "Mary should be the author now"
+
-    assert_equal "DavidHeinemeierHansson", @page.revisions.first.author, "David was the first author"
+  def test_revise
+    @page.revise('HisWay would be MyWay in kinda lame', Time.local(2004, 4, 4, 16, 55), 'MarianneSyhler')
+    assert_equal 2, @page.revisions.length, 'Should have two revisions'
+    assert_equal 'MarianneSyhler', @page.author, 'Mary should be the author now'
+    assert_equal 'DavidHeinemeierHansson', @page.revisions.first.author, 'David was the first author'
+  end
+  
+  def test_revise_continous_revision
+    @page.revise('HisWay would be MyWay in kinda lame', Time.local(2004, 4, 4, 16, 55), 'MarianneSyhler')
+    assert_equal 2, @page.revisions.length
+
+    @page.revise('HisWay would be MyWay in kinda update', Time.local(2004, 4, 4, 16, 57), 'MarianneSyhler')
+    assert_equal 2, @page.revisions.length
+    assert_equal 'HisWay would be MyWay in kinda update', @page.revisions.last.content
+    assert_equal Time.local(2004, 4, 4, 16, 57), @page.revisions.last.created_at
+
+    @page.revise('HisWay would be MyWay in the house', Time.local(2004, 4, 4, 16, 58), 'DavidHeinemeierHansson')
+    assert_equal 3, @page.revisions.length
+    assert_equal 'HisWay would be MyWay in the house', @page.revisions.last.content
+
+    @page.revise('HisWay would be MyWay in my way', Time.local(2004, 4, 4, 17, 30), 'DavidHeinemeierHansson')
+    assert_equal 4, @page.revisions.length
+  end
+
+  def test_revise_content_unchanged
+    last_revision_before = @page.revisions.last
+    revisions_number_before = @page.revisions.size
+  
+    assert_raises(Instiki::ValidationError) { 
+      @page.revise(@page.revisions.last.content.dup, Time.now, 'AlexeyVerkhovsky')
+    }
+    
+    assert_same last_revision_before, @page.revisions.last
+    assert_equal revisions_number_before, @page.revisions.size
   end
 
   def test_rollback
@@ -59,20 +89,4 @@ class PageTest < Test::Unit::TestCase
     assert_equal "spot two", @page.content
   end
   
-  def test_continous_revision
-    @page.revise("HisWay would be MyWay in kinda lame", Time.local(2004, 4, 4, 16, 55), "MarianneSyhler")
-    assert_equal 2, @page.revisions.length
-
-    @page.revise("HisWay would be MyWay in kinda update", Time.local(2004, 4, 4, 16, 57), "MarianneSyhler")
-    assert_equal 2, @page.revisions.length
-    assert_equal "HisWay would be MyWay in kinda update", @page.revisions.last.content
-    assert_equal Time.local(2004, 4, 4, 16, 57), @page.revisions.last.created_at
-
-    @page.revise("HisWay would be MyWay in the house", Time.local(2004, 4, 4, 16, 58), "DavidHeinemeierHansson")
-    assert_equal 3, @page.revisions.length
-    assert_equal "HisWay would be MyWay in the house", @page.revisions.last.content
-
-    @page.revise("HisWay would be MyWay in my way", Time.local(2004, 4, 4, 17, 30), "DavidHeinemeierHansson")
-    assert_equal 4, @page.revisions.length
-  end
 end