Raise type inferred from failed dispatch+privacy. IssueID: michaeledg…

…ar#2
rkh · Jul 26, 2011 · d42ed31 · d42ed31
1 parent a172091
commit d42ed31
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Showing 5 changed files with 83 additions and 0 deletions.
diff --git a/lib/laser/analysis/control_flow/constant_propagation.rb b/lib/laser/analysis/control_flow/constant_propagation.rb
@@ -394,10 +394,17 @@ def raisability_for_templates(possible_dispatches, cartesian, ignore_privacy)
                             then Frequency::NEVER
                             else Frequency.for_samples(seen_private, seen_public)
                             end
+            if fails_privacy == Frequency::ALWAYS
+              raise_type = ClassRegistry['NoMethodError'].as_type
+            end
+            if fails_lookup > Frequency::NEVER
+              raise_type |= ClassRegistry['NoMethodError'].as_type
+            end
             raised = Frequency.for_samples(seen_raise, seen_succeed)
             raise_freq = [fails_privacy, raised, fails_lookup].max
           else
             raise_freq = Frequency::ALWAYS  # no method!
+            raise_type = ClassRegistry['NoMethodError'].as_type
           end
           [raise_freq, raise_type]
         end

diff --git a/lib/laser/standard_library/bignum.rb b/lib/laser/standard_library/bignum.rb
@@ -74,6 +74,8 @@ def ===(num)
   # pure: true
   # builtin: true
   # returns: Boolean
+  # num: Numeric
+  # raises: never
   def >(num)
   end
   # pure: true

diff --git a/lib/laser/standard_library/fixnum.rb b/lib/laser/standard_library/fixnum.rb
@@ -73,6 +73,8 @@ def ===(num)
   # pure: true
   # builtin: true
   # returns: Boolean
+  # num: Numeric
+  # raises: never
   def >(num)
   end
   # pure: true

diff --git a/spec/analysis_specs/control_flow_specs/raise_properties_spec.rb b/spec/analysis_specs/control_flow_specs/raise_properties_spec.rb
@@ -165,5 +165,40 @@ def silly(x)
         [Types::FIXNUM],
         Types::NILCLASS).should == Frequency::ALWAYS
   end
+
+  it 'can infer a guaranteed NoMethodError from privacy violations' do
+    g = cfg <<-EOF
+class RInfer5
+  def foo
+  end
+  private :foo
+
+  def bar
+    self.foo  # error!
+  end
+end
+EOF
+    method = ClassRegistry['RInfer5'].instance_method('bar')
+    method.raise_frequency_for_types(
+        Utilities.type_for(ClassRegistry['RInfer5'])).should == Frequency::ALWAYS
+  end
+
+  it 'can infer a potential lookup failure when a successful one exists' do
+    g = cfg <<-EOF
+class RInfer6
+  def bar
+    if gets.size > 0
+      x = 'hello'
+    else
+      x = 5
+    end
+    x.intern  # error sometimes
+  end
+end
+EOF
+    method = ClassRegistry['RInfer6'].instance_method('bar')
+    method.raise_frequency_for_types(
+        Utilities.type_for(ClassRegistry['RInfer6'])).should == Frequency::MAYBE
+  end
 end
 
diff --git a/spec/analysis_specs/control_flow_specs/raise_type_inference_spec.rb b/spec/analysis_specs/control_flow_specs/raise_type_inference_spec.rb
@@ -146,4 +146,41 @@ def silly(x)
         [Types::FIXNUM],
         Types::NILCLASS).should equal_type(ClassRegistry['NoMethodError'].as_type)
   end
+
+  it 'can infer a guaranteed NoMethodError from privacy violations' do
+    g = cfg <<-EOF
+class RTInfer5
+  def foo
+  end
+  private :foo
+  
+  def bar
+    self.foo  # error!
+  end
+end
+EOF
+    method = ClassRegistry['RTInfer5'].instance_method('bar')
+    method.raise_type_for_types(
+        Utilities.type_for(ClassRegistry['RTInfer5'])).should(
+          equal_type(ClassRegistry['NoMethodError'].as_type))
+  end
+
+  it 'can infer a potential lookup failure when a successful one exists' do
+    g = cfg <<-EOF
+class RTInfer6
+  def bar
+    if gets.size > 0
+      x = 'hello'
+    else
+      x = 5
+    end
+    x.intern  # error sometimes
+  end
+end
+EOF
+    method = ClassRegistry['RTInfer6'].instance_method('bar')
+    method.raise_type_for_types(
+        Utilities.type_for(ClassRegistry['RTInfer6'])).should(
+          equal_type(ClassRegistry['NoMethodError'].as_type))
+  end
 end