More tests, More doc, less duplication

Author: rocky

mathics/builtin/scoping.py

@@ -60,17 +60,26 @@ class With(Builtin):
     <dl>
 
     <dt>'With[{$x$=$x0$, $y$=$y0$, ...}, $expr$]'
-        <dd>specifies that all occurrences of the symbols $x$, $y$, ... in $expr$ should be replaced by $x0$, $y0$, ... 
+        <dd>specifies that all occurrences of the symbols $x$, $y$, ... in $expr$ should be replaced by $x0$, $y0$, ...
     </dl>
 
     >> n = 10
      = 10
+
+    Evaluate an expression with x locally set to 5:
     >> With[{n = 5}, n ^ 2]
      = 25
     >> n
      = 10
+
+    'With' works even without evaluation:
+    >> With[{x = a}, (1 + x^2) &]
+     = 1 + a ^ 2&
+
+    Use 'With' to insert values into held expressions
     >> With[{x=y}, Hold[x]]
      = Hold[y]
+
     >> Table[With[{i=j}, Hold[i]],{j,1,4}]
      = {Hold[1], Hold[2], Hold[3], Hold[4]}
     >> x=5; With[{x=x}, Hold[x]]
@@ -624,7 +633,7 @@ class BeginPackage(Builtin):
              System`Private`$ContextPathStack =
                  Append[System`Private`$ContextPathStack, $ContextPath];
              $ContextPath = {context, "System`"};
-             $Packages = If[MemberQ[System`$Packages,$Context], 
+             $Packages = If[MemberQ[System`$Packages,$Context],
                             None,
                             System`$Packages=Join[{$Context}, System`$Packages]];
              Protect[System`Private`$ContextPathStack, System`$Packages];

test/helper.py

@@ -1,3 +1,6 @@
+from mathics.core.parser import parse, SingleLineFeeder
+from mathics.core.definitions import Definitions
+from mathics.core.evaluation import Evaluation
 from mathics.session import MathicsSession
 
 session = MathicsSession(add_builtin=True, catch_interrupt=False)

test/test_combinatorica.py

@@ -1,13 +1,6 @@
 # -*- coding: utf-8 -*-
 from .helper import session, check_evaluation
 
-import sys
-from mathics.core.parser import parse, SingleLineFeeder
-from mathics.core.definitions import Definitions
-from mathics.core.evaluation import Evaluation
-import pytest
-
-
 def test_combinatorica():
     session.evaluate(
         """

test/test_control.py

@@ -1,14 +1,7 @@
 # -*- coding: utf-8 -*-
 from .helper import session, check_evaluation
 
-import sys
-from mathics.core.parser import parse, SingleLineFeeder
-from mathics.core.definitions import Definitions
-from mathics.core.evaluation import Evaluation
-import pytest
-
-
-def test_control():
+def test_catch():
     session.evaluate(
         """
         (* Define a function that can "throw an exception": *)

test/test_evaluation.py

@@ -46,7 +46,7 @@
         ),
     ],
 )
-def check_evaluation(str_expr: str, str_expected: str, message=""):
+def test_evaluation(str_expr: str, str_expected: str, message=""):
     result = session.evaluate(str_expr)
     expected = session.evaluate(str_expected)