Add checks to ensure statement unit conversions are idempotent

6 files changed, 379 insertions, 89 deletions

diff --git a/gerber/excellon.py b/gerber/excellon.py
index 0f70de7..f994b67 100755
--- a/gerber/excellon.py
+++ b/gerber/excellon.py
@@ -219,6 +219,9 @@ class ExcellonParser(object):
         with open(filename, 'r') as f:

             for line in f:

                 self._parse(line.strip())

+                

+        for stmt in self.statements:

+            stmt.units = self.units

         return ExcellonFile(self.statements, self.tools, self.hits,

                             self._settings(), filename)

 

diff --git a/gerber/excellon_statements.py b/gerber/excellon_statements.py
index 95347d1..31a3c72 100644
--- a/gerber/excellon_statements.py
+++ b/gerber/excellon_statements.py
@@ -39,6 +39,9 @@ __all__ = ['ExcellonTool', 'ToolSelectionStmt', 'CoordinateStmt',
 class ExcellonStatement(object):
     """ Excellon Statement abstract base class
     """
+    
+    units = 'inch'
+     
     @classmethod
     def from_excellon(cls, line):
         raise NotImplementedError('from_excellon must be implemented in a '
@@ -47,12 +50,11 @@ class ExcellonStatement(object):
     def to_excellon(self, settings=None):
         raise NotImplementedError('to_excellon must be implemented in a '
                                   'subclass')
-
     def to_inch(self):
-        pass
+        self.units = 'inch'
 
     def to_metric(self):
-        pass
+        self.units = 'metric'
 
     def offset(self, x_offset=0, y_offset=0):
         pass
@@ -274,7 +276,9 @@ class CoordinateStmt(ExcellonStatement):
         else:
             y_coord = parse_gerber_value(line.strip(' Y'), settings.format,
                                          settings.zero_suppression)
-        return cls(x_coord, y_coord)
+        c = cls(x_coord, y_coord)
+        c.units = settings.units
+        return c
 
     def __init__(self, x=None, y=None):
         self.x = x
@@ -291,16 +295,20 @@ class CoordinateStmt(ExcellonStatement):
         return stmt
 
     def to_inch(self):
-        if self.x is not None:
-            self.x = inch(self.x)
-        if self.y is not None:
-            self.y = inch(self.y)
+        if self.units == 'metric':
+            self.units = 'inch'
+            if self.x is not None:
+                self.x = inch(self.x)
+            if self.y is not None:
+                self.y = inch(self.y)
 
     def to_metric(self):
-        if self.x is not None:
-            self.x = metric(self.x)
-        if self.y is not None:
-            self.y = metric(self.y)
+        if self.units == 'inch':
+            self.units = 'metric'
+            if self.x is not None:
+                self.x = metric(self.x)
+            if self.y is not None:
+                self.y = metric(self.y)
 
     def offset(self, x_offset=0, y_offset=0):
         if self.x is not None:
@@ -332,7 +340,9 @@ class RepeatHoleStmt(ExcellonStatement):
         ydelta = (parse_gerber_value(stmt['ydelta'], settings.format,
                                      settings.zero_suppression)
                   if stmt['ydelta'] is not '' else None)
-        return cls(count, xdelta, ydelta)
+        c = cls(count, xdelta, ydelta)
+        c.units = settings.units
+        return c
 
     def __init__(self, count, xdelta=0.0, ydelta=0.0):
         self.count = count
@@ -350,16 +360,20 @@ class RepeatHoleStmt(ExcellonStatement):
         return stmt
 
     def to_inch(self):
-        if self.xdelta is not None:
-            self.xdelta = inch(self.xdelta)
-        if self.ydelta is not None:
-            self.ydelta = inch(self.ydelta)
+        if self.units == 'metric':
+            self.units = 'inch'
+            if self.xdelta is not None:
+                self.xdelta = inch(self.xdelta)
+            if self.ydelta is not None:
+                self.ydelta = inch(self.ydelta)
 
     def to_metric(self):
-        if self.xdelta is not None:
-            self.xdelta = metric(self.xdelta)
-        if self.ydelta is not None:
-            self.ydelta = metric(self.ydelta)
+        if self.units == 'inch':
+            self.units = 'metric'
+            if self.xdelta is not None:
+                self.xdelta = metric(self.xdelta)
+            if self.ydelta is not None:
+                self.ydelta = metric(self.ydelta)
 
     def __str__(self):
         return '<Repeat Hole: %d times, offset X: %g Y: %g>' % (
@@ -421,7 +435,9 @@ class EndOfProgramStmt(ExcellonStatement):
         y = (parse_gerber_value(stmt['y'], settings.format,
                                 settings.zero_suppression)
              if stmt['y'] is not '' else None)
-        return cls(x, y)
+        c = cls(x, y)
+        c.units = settings.units
+        return c
 
     def __init__(self, x=None, y=None):
         self.x = x
@@ -436,16 +452,20 @@ class EndOfProgramStmt(ExcellonStatement):
         return stmt
 
     def to_inch(self):
-        if self.x is not None:
-            self.x = inch(self.x)
-        if self.y is not None:
-            self.y = inch(self.y)
+        if self.units == 'metric':
+            self.units = 'inch'
+            if self.x is not None:
+                self.x = inch(self.x)
+            if self.y is not None:
+                self.y = inch(self.y)
 
     def to_metric(self):
-        if self.x is not None:
-            self.x = metric(self.x)
-        if self.y is not None:
-            self.y = metric(self.y)
+        if self.units == 'inch':
+            self.units = 'metric'
+            if self.x is not None:
+                self.x = metric(self.x)
+            if self.y is not None:
+                self.y = metric(self.y)
 
     def offset(self, x_offset=0, y_offset=0):
         if self.x is not None:
diff --git a/gerber/gerber_statements.py b/gerber/gerber_statements.py
index f2fc970..a198bb9 100644
--- a/gerber/gerber_statements.py
+++ b/gerber/gerber_statements.py
@@ -43,8 +43,9 @@ class Statement(object):
     type : string
         String identifying the statement type.
     """
-    def __init__(self, stype):
+    def __init__(self, stype, units='inch'):
         self.type = stype
+        self.units = units
 
     def __str__(self):
         s = "<{0} ".format(self.__class__.__name__)
@@ -56,10 +57,10 @@ class Statement(object):
         return s
 
     def to_inch(self):
-        pass
+        self.units = 'inch'
 
     def to_metric(self):
-        pass
+        self.units = 'metric'
 
     def offset(self, x_offset=0, y_offset=0):
         pass
@@ -156,6 +157,8 @@ class FSParamStmt(ParamStmt):
 
         return '%FS{0}{1}X{2}Y{3}*%'.format(zero_suppression, notation, fmt, fmt)
 
+    
+
     def __str__(self):
         return ('<Format Spec: %d:%d %s zero suppression %s notation>' %
                 (self.format[0], self.format[1], self.zero_suppression, self.notation))
@@ -295,10 +298,14 @@ class ADParamStmt(ParamStmt):
             self.modifiers = [tuple()]
 
     def to_inch(self):
-        self.modifiers = [tuple([inch(x) for x in modifier]) for modifier in self.modifiers]
+        if self.units == 'metric':
+            self.units = 'inch'    
+            self.modifiers = [tuple([inch(x) for x in modifier]) for modifier in self.modifiers]
 
     def to_metric(self):
-        self.modifiers = [tuple([metric(x) for x in modifier]) for modifier in self.modifiers]
+        if self.units == 'inch':
+            self.units = 'metric'    
+            self.modifiers = [tuple([metric(x) for x in modifier]) for modifier in self.modifiers]
 
     def to_gerber(self, settings=None):
         if any(self.modifiers):
@@ -383,12 +390,16 @@ class AMParamStmt(ParamStmt):
                 self.primitives.append(AMUnsupportPrimitive.from_gerber(primitive))
 
     def to_inch(self):
-        for primitive in self.primitives:
-            primitive.to_inch()
+        if self.units == 'metric':
+            self.units = 'inch'
+            for primitive in self.primitives:
+                primitive.to_inch()
 
     def to_metric(self):
-        for primitive in self.primitives:
-            primitive.to_metric()
+        if self.units == 'inch':
+            self.units = 'metric'
+            for primitive in self.primitives:
+                primitive.to_metric()
 
     def to_gerber(self, settings=None):
         return '%AM{0}*{1}*%'.format(self.name, self.macro)
@@ -630,16 +641,20 @@ class OFParamStmt(ParamStmt):
         return ret + '*%'
 
     def to_inch(self):
-        if self.a is not None:
-            self.a = inch(self.a)
-        if self.b is not None:
-            self.b = inch(self.b)
+        if self.units == 'metric':
+            self.units = 'inch'
+            if self.a is not None:
+                self.a = inch(self.a)
+            if self.b is not None:
+                self.b = inch(self.b)
 
     def to_metric(self):
-        if self.a is not None:
-            self.a = metric(self.a)
-        if self.b is not None:
-            self.b = metric(self.b)
+        if self.units == 'inch':
+            self.units = 'metric'
+            if self.a is not None:
+                self.a = metric(self.a)
+            if self.b is not None:
+                self.b = metric(self.b)
 
     def offset(self, x_offset=0, y_offset=0):
         if self.a is not None:
@@ -700,16 +715,20 @@ class SFParamStmt(ParamStmt):
         return ret + '*%'
 
     def to_inch(self):
-        if self.a is not None:
-            self.a = inch(self.a)
-        if self.b is not None:
-            self.b = inch(self.b)
+        if self.units == 'metric':
+            self.units = 'inch'
+            if self.a is not None:
+                self.a = inch(self.a)
+            if self.b is not None:
+                self.b = inch(self.b)
 
     def to_metric(self):
-        if self.a is not None:
-            self.a = metric(self.a)
-        if self.b is not None:
-            self.b = metric(self.b)
+        if self.units == 'inch':
+            self.units = 'metric'
+            if self.a is not None:
+                self.a = metric(self.a)
+            if self.b is not None:
+                self.b = metric(self.b)
 
     def offset(self, x_offset=0, y_offset=0):
         if self.a is not None:
@@ -871,28 +890,32 @@ class CoordStmt(Statement):
         return ret + '*'
 
     def to_inch(self):
-        if self.x is not None:
-            self.x = inch(self.x)
-        if self.y is not None:
-            self.y = inch(self.y)
-        if self.i is not None:
-            self.i = inch(self.i)
-        if self.j is not None:
-            self.j = inch(self.j)
-        if self.function == "G71":
-            self.function = "G70"
+        if self.units == 'metric':
+            self.units = 'inch'
+            if self.x is not None:
+                self.x = inch(self.x)
+            if self.y is not None:
+                self.y = inch(self.y)
+            if self.i is not None:
+                self.i = inch(self.i)
+            if self.j is not None:
+                self.j = inch(self.j)
+            if self.function == "G71":
+                self.function = "G70"
 
     def to_metric(self):
-        if self.x is not None:
-            self.x = metric(self.x)
-        if self.y is not None:
-            self.y = metric(self.y)
-        if self.i is not None:
-            self.i = metric(self.i)
-        if self.j is not None:
-            self.j = metric(self.j)
-        if self.function == "G70":
-            self.function = "G71"
+        if self.units == 'inch':
+            self.units = 'metric'
+            if self.x is not None:
+                self.x = metric(self.x)
+            if self.y is not None:
+                self.y = metric(self.y)
+            if self.i is not None:
+                self.i = metric(self.i)
+            if self.j is not None:
+                self.j = metric(self.j)
+            if self.function == "G70":
+                self.function = "G71"
 
     def offset(self, x_offset=0, y_offset=0):
         if self.x is not None:
diff --git a/gerber/rs274x.py b/gerber/rs274x.py
index 3dcddb4..20baaa7 100644
--- a/gerber/rs274x.py
+++ b/gerber/rs274x.py
@@ -214,6 +214,10 @@ class GerberParser(object):
             self.evaluate(stmt)
             self.statements.append(stmt)
 
+        # Initialize statement units
+        for stmt in self.statements:
+            stmt.units = self.settings.units
+
         return GerberFile(self.statements, self.settings, self.primitives, filename)
 
     def dump_json(self):
diff --git a/gerber/tests/test_excellon_statements.py b/gerber/tests/test_excellon_statements.py
index ada5194..1e8ef91 100644
--- a/gerber/tests/test_excellon_statements.py
+++ b/gerber/tests/test_excellon_statements.py
@@ -150,7 +150,13 @@ def test_coordinatestmt_factory():
     assert_equal(stmt.x, 0.9660)
     assert_equal(stmt.y, 0.4639)
     assert_equal(stmt.to_excellon(settings), "X9660Y4639")
-
+    assert_equal(stmt.units, 'inch')
+    
+    settings.units = 'metric'
+    stmt = CoordinateStmt.from_excellon(line, settings)
+    assert_equal(stmt.units, 'metric')
+    
+    
 def test_coordinatestmt_dump():
     """ Test CoordinateStmt to_excellon()
     """
@@ -164,11 +170,40 @@ def test_coordinatestmt_dump():
         assert_equal(stmt.to_excellon(settings), line)
 
 def test_coordinatestmt_conversion():
-    stmt = CoordinateStmt.from_excellon('X254Y254', FileSettings())
+    
+    settings = FileSettings()
+    settings.units = 'metric'
+    stmt = CoordinateStmt.from_excellon('X254Y254', settings)
+    
+    #No effect
+    stmt.to_metric()
+    assert_equal(stmt.x, 25.4)
+    assert_equal(stmt.y, 25.4)
+    
     stmt.to_inch()
+    assert_equal(stmt.units, 'inch')
     assert_equal(stmt.x, 1.)
     assert_equal(stmt.y, 1.)
-    stmt = CoordinateStmt.from_excellon('X01Y01', FileSettings())
+    
+    #No effect
+    stmt.to_inch()
+    assert_equal(stmt.x, 1.)
+    assert_equal(stmt.y, 1.)
+    
+    settings.units = 'inch'
+    stmt = CoordinateStmt.from_excellon('X01Y01', settings)
+    
+    #No effect
+    stmt.to_inch()
+    assert_equal(stmt.x, 1.)
+    assert_equal(stmt.y, 1.)
+    
+    stmt.to_metric()
+    assert_equal(stmt.units, 'metric')
+    assert_equal(stmt.x, 25.4)
+    assert_equal(stmt.y, 25.4)
+    
+    #No effect
     stmt.to_metric()
     assert_equal(stmt.x, 25.4)
     assert_equal(stmt.y, 25.4)
@@ -194,10 +229,14 @@ def test_coordinatestmt_string():
 
 
 def test_repeathole_stmt_factory():
-    stmt = RepeatHoleStmt.from_excellon('R0004X015Y32', FileSettings(zeros='leading'))
+    stmt = RepeatHoleStmt.from_excellon('R0004X015Y32', FileSettings(zeros='leading', units='inch'))
     assert_equal(stmt.count, 4)
     assert_equal(stmt.xdelta, 1.5)
     assert_equal(stmt.ydelta, 32)
+    assert_equal(stmt.units, 'inch')
+    
+    stmt = RepeatHoleStmt.from_excellon('R0004X015Y32', FileSettings(zeros='leading', units='metric'))
+    assert_equal(stmt.units, 'metric')
 
 def test_repeatholestmt_dump():
     line = 'R4X015Y32'
@@ -206,13 +245,40 @@ def test_repeatholestmt_dump():
 
 def test_repeatholestmt_conversion():
     line = 'R4X0254Y254'
-    stmt = RepeatHoleStmt.from_excellon(line, FileSettings())
+    settings = FileSettings()
+    settings.units = 'metric'
+    stmt = RepeatHoleStmt.from_excellon(line, settings)
+    
+    #No effect
+    stmt.to_metric()
+    assert_equal(stmt.xdelta, 2.54)
+    assert_equal(stmt.ydelta, 25.4)
+    
+    stmt.to_inch()
+    assert_equal(stmt.units, 'inch')
+    assert_equal(stmt.xdelta, 0.1)
+    assert_equal(stmt.ydelta, 1.)
+    
+    #no effect
     stmt.to_inch()
     assert_equal(stmt.xdelta, 0.1)
     assert_equal(stmt.ydelta, 1.)
 
     line = 'R4X01Y1'
-    stmt = RepeatHoleStmt.from_excellon(line, FileSettings())
+    settings.units = 'inch'
+    stmt = RepeatHoleStmt.from_excellon(line, settings)
+    
+    #no effect
+    stmt.to_inch()
+    assert_equal(stmt.xdelta, 1.)
+    assert_equal(stmt.ydelta, 10.)
+    
+    stmt.to_metric()
+    assert_equal(stmt.units, 'metric')
+    assert_equal(stmt.xdelta, 25.4)
+    assert_equal(stmt.ydelta, 254.)
+    
+    #No effect
     stmt.to_metric()
     assert_equal(stmt.xdelta, 25.4)
     assert_equal(stmt.ydelta, 254.)
@@ -258,12 +324,16 @@ def test_rewindstop_stmt():
     assert_equal(stmt.to_excellon(None), '%')
 
 def test_endofprogramstmt_factory():
-    stmt = EndOfProgramStmt.from_excellon('M30X01Y02', FileSettings())
+    settings = FileSettings(units='inch')
+    stmt = EndOfProgramStmt.from_excellon('M30X01Y02', settings)
     assert_equal(stmt.x, 1.)
     assert_equal(stmt.y, 2.)
-    stmt = EndOfProgramStmt.from_excellon('M30X01', FileSettings())
+    assert_equal(stmt.units, 'inch')
+    settings.units = 'metric'
+    stmt = EndOfProgramStmt.from_excellon('M30X01', settings)
     assert_equal(stmt.x, 1.)
     assert_equal(stmt.y, None)
+    assert_equal(stmt.units, 'metric')
     stmt = EndOfProgramStmt.from_excellon('M30Y02', FileSettings())
     assert_equal(stmt.x, None)
     assert_equal(stmt.y, 2.)
@@ -275,12 +345,38 @@ def test_endofprogramStmt_dump():
         assert_equal(stmt.to_excellon(FileSettings()), line)
 
 def test_endofprogramstmt_conversion():
-    stmt = EndOfProgramStmt.from_excellon('M30X0254Y254', FileSettings())
+    settings = FileSettings()
+    settings.units = 'metric'
+    stmt = EndOfProgramStmt.from_excellon('M30X0254Y254', settings)
+    #No effect
+    stmt.to_metric()
+    assert_equal(stmt.x, 2.54)
+    assert_equal(stmt.y, 25.4)
+    
+    stmt.to_inch()
+    assert_equal(stmt.units, 'inch')
+    assert_equal(stmt.x, 0.1)
+    assert_equal(stmt.y, 1.0)
+    
+    #No effect
     stmt.to_inch()
     assert_equal(stmt.x, 0.1)
     assert_equal(stmt.y, 1.0)
 
-    stmt = EndOfProgramStmt.from_excellon('M30X01Y1', FileSettings())
+    settings.units = 'inch'
+    stmt = EndOfProgramStmt.from_excellon('M30X01Y1', settings)
+    
+    #No effect
+    stmt.to_inch()
+    assert_equal(stmt.x, 1.)
+    assert_equal(stmt.y, 10.0)
+    
+    stmt.to_metric()
+    assert_equal(stmt.units, 'metric')
+    assert_equal(stmt.x, 25.4)
+    assert_equal(stmt.y, 254.)
+    
+    #No effect
     stmt.to_metric()
     assert_equal(stmt.x, 25.4)
     assert_equal(stmt.y, 254.)
diff --git a/gerber/tests/test_gerber_statements.py b/gerber/tests/test_gerber_statements.py
index a8a4a1a..f3249b1 100644
--- a/gerber/tests/test_gerber_statements.py
+++ b/gerber/tests/test_gerber_statements.py
@@ -10,10 +10,13 @@ from ..cam import FileSettings
 def test_Statement_smoketest():
     stmt = Statement('Test')
     assert_equal(stmt.type, 'Test')
+    stmt.to_metric()
+    assert_in('units=metric', str(stmt))
     stmt.to_inch()
+    assert_in('units=inch', str(stmt))
     stmt.to_metric()
     stmt.offset(1, 1)
-    assert_equal(str(stmt), '<Statement type=Test>')
+    assert_in('type=Test',str(stmt))
 
 def test_FSParamStmt_factory():
     """ Test FSParamStruct factory
@@ -220,12 +223,38 @@ def test_OFParamStmt_dump():
 def test_OFParamStmt_conversion():
     stmt = {'param': 'OF', 'a': '2.54', 'b': '25.4'}
     of = OFParamStmt.from_dict(stmt)
+    of.units='metric'
+
+    # No effect
+    of.to_metric()
+    assert_equal(of.a, 2.54)
+    assert_equal(of.b, 25.4)
+
+    of.to_inch()
+    assert_equal(of.units, 'inch')
+    assert_equal(of.a, 0.1)
+    assert_equal(of.b, 1.0)
+
+    #No effect
     of.to_inch()
     assert_equal(of.a, 0.1)
     assert_equal(of.b, 1.0)
 
     stmt = {'param': 'OF', 'a': '0.1', 'b': '1.0'}
     of = OFParamStmt.from_dict(stmt)
+    of.units = 'inch'
+
+    #No effect
+    of.to_inch()
+    assert_equal(of.a, 0.1)
+    assert_equal(of.b, 1.0)
+
+    of.to_metric()
+    assert_equal(of.units, 'metric')
+    assert_equal(of.a, 2.54)
+    assert_equal(of.b, 25.4)
+
+    #No effect
     of.to_metric()
     assert_equal(of.a, 2.54)
     assert_equal(of.b, 25.4)
@@ -261,12 +290,38 @@ def test_SFParamStmt_dump():
 def test_SFParamStmt_conversion():
     stmt = {'param': 'OF', 'a': '2.54', 'b': '25.4'}
     of = SFParamStmt.from_dict(stmt)
+    of.units = 'metric'
+    of.to_metric()
+
+    #No effect
+    assert_equal(of.a, 2.54)
+    assert_equal(of.b, 25.4)
+
+    of.to_inch()
+    assert_equal(of.units, 'inch')
+    assert_equal(of.a, 0.1)
+    assert_equal(of.b, 1.0)
+
+    #No effect
     of.to_inch()
     assert_equal(of.a, 0.1)
     assert_equal(of.b, 1.0)
 
     stmt = {'param': 'OF', 'a': '0.1', 'b': '1.0'}
     of = SFParamStmt.from_dict(stmt)
+    of.units = 'inch'
+
+    #No effect
+    of.to_inch()
+    assert_equal(of.a, 0.1)
+    assert_equal(of.b, 1.0)
+
+    of.to_metric()
+    assert_equal(of.units, 'metric')
+    assert_equal(of.a, 2.54)
+    assert_equal(of.b, 25.4)
+
+    #No effect
     of.to_metric()
     assert_equal(of.a, 2.54)
     assert_equal(of.b, 25.4)
@@ -350,7 +405,21 @@ def testAMParamStmt_conversion():
     name = 'POLYGON'
     macro = '5,1,8,25.4,25.4,25.4,0*'
     s = AMParamStmt.from_dict({'param': 'AM', 'name': name, 'macro': macro })
+
     s.build()
+    s.units = 'metric'
+
+    #No effect
+    s.to_metric()
+    assert_equal(s.primitives[0].position, (25.4, 25.4))
+    assert_equal(s.primitives[0].diameter, 25.4)
+
+    s.to_inch()
+    assert_equal(s.units, 'inch')
+    assert_equal(s.primitives[0].position, (1., 1.))
+    assert_equal(s.primitives[0].diameter, 1.)
+
+    #No effect
     s.to_inch()
     assert_equal(s.primitives[0].position, (1., 1.))
     assert_equal(s.primitives[0].diameter, 1.)
@@ -358,6 +427,19 @@ def testAMParamStmt_conversion():
     macro = '5,1,8,1,1,1,0*'
     s = AMParamStmt.from_dict({'param': 'AM', 'name': name, 'macro': macro })
     s.build()
+    s.units = 'inch'
+
+    #No effect
+    s.to_inch()
+    assert_equal(s.primitives[0].position, (1., 1.))
+    assert_equal(s.primitives[0].diameter, 1.)
+
+    s.to_metric()
+    assert_equal(s.units, 'metric')
+    assert_equal(s.primitives[0].position, (25.4, 25.4))
+    assert_equal(s.primitives[0].diameter, 25.4)
+
+    #No effect
     s.to_metric()
     assert_equal(s.primitives[0].position, (25.4, 25.4))
     assert_equal(s.primitives[0].diameter, 25.4)
@@ -535,10 +617,10 @@ def test_statement_string():
     """ Test Statement.__str__()
     """
     stmt = Statement('PARAM')
-    assert_equal(str(stmt), '<Statement type=PARAM>')
+    assert_in('type=PARAM', str(stmt))
     stmt.test='PASS'
-    assert_true('test=PASS' in str(stmt))
-    assert_true('type=PARAM' in str(stmt))
+    assert_in('test=PASS', str(stmt))
+    assert_in('type=PARAM', str(stmt))
 
 def test_ADParamStmt_factory():
     """ Test ADParamStmt factory
@@ -556,12 +638,37 @@ def test_ADParamStmt_factory():
 def test_ADParamStmt_conversion():
     stmt = {'param': 'AD', 'd': 0, 'shape': 'C', 'modifiers': '25.4X25.4,25.4X25.4'}
     ad = ADParamStmt.from_dict(stmt)
+    ad.units = 'metric'
+
+    #No effect
+    ad.to_metric()
+    assert_equal(ad.modifiers[0], (25.4, 25.4))
+    assert_equal(ad.modifiers[1], (25.4, 25.4))
+
+    ad.to_inch()
+    assert_equal(ad.units, 'inch')
+    assert_equal(ad.modifiers[0], (1., 1.))
+    assert_equal(ad.modifiers[1], (1., 1.))
+
+    #No effect
     ad.to_inch()
     assert_equal(ad.modifiers[0], (1., 1.))
     assert_equal(ad.modifiers[1], (1., 1.))
 
     stmt = {'param': 'AD', 'd': 0, 'shape': 'C', 'modifiers': '1X1,1X1'}
     ad = ADParamStmt.from_dict(stmt)
+    ad.units = 'inch'
+
+    #No effect
+    ad.to_inch()
+    assert_equal(ad.modifiers[0], (1., 1.))
+    assert_equal(ad.modifiers[1], (1., 1.))
+
+    ad.to_metric()
+    assert_equal(ad.modifiers[0], (25.4, 25.4))
+    assert_equal(ad.modifiers[1], (25.4, 25.4))
+
+    #No effect
     ad.to_metric()
     assert_equal(ad.modifiers[0], (25.4, 25.4))
     assert_equal(ad.modifiers[1], (25.4, 25.4))
@@ -646,6 +753,25 @@ def test_coordstmt_dump():
 
 def test_coordstmt_conversion():
     cs = CoordStmt('G71', 25.4, 25.4, 25.4, 25.4, 'D01', FileSettings())
+    cs.units = 'metric'
+
+    #No effect
+    cs.to_metric()
+    assert_equal(cs.x, 25.4)
+    assert_equal(cs.y, 25.4)
+    assert_equal(cs.i, 25.4)
+    assert_equal(cs.j, 25.4)
+    assert_equal(cs.function, 'G71')
+
+    cs.to_inch()
+    assert_equal(cs.units, 'inch')
+    assert_equal(cs.x, 1.)
+    assert_equal(cs.y, 1.)
+    assert_equal(cs.i, 1.)
+    assert_equal(cs.j, 1.)
+    assert_equal(cs.function, 'G70')
+
+    #No effect
     cs.to_inch()
     assert_equal(cs.x, 1.)
     assert_equal(cs.y, 1.)
@@ -654,6 +780,24 @@ def test_coordstmt_conversion():
     assert_equal(cs.function, 'G70')
 
     cs = CoordStmt('G70', 1., 1., 1., 1., 'D01', FileSettings())
+    cs.units = 'inch'
+
+    #No effect
+    cs.to_inch()
+    assert_equal(cs.x, 1.)
+    assert_equal(cs.y, 1.)
+    assert_equal(cs.i, 1.)
+    assert_equal(cs.j, 1.)
+    assert_equal(cs.function, 'G70')
+
+    cs.to_metric()
+    assert_equal(cs.x, 25.4)
+    assert_equal(cs.y, 25.4)
+    assert_equal(cs.i, 25.4)
+    assert_equal(cs.j, 25.4)
+    assert_equal(cs.function, 'G71')
+
+    #No effect
     cs.to_metric()
     assert_equal(cs.x, 25.4)
     assert_equal(cs.y, 25.4)