starlarkstruct: add 'module' type, and use it for assert module (#91)

...instead of struct, which is more suited to dynamic values.

This type will be used for Stargo (see wip-stargo branch).
For example, this load statement

  load("go", http="net/http", json="encoding/json")

would load two modules.

2 files changed, 22 insertions, 22 deletions

diff --git a/starlarktest/assert.star b/starlarktest/assert.star
index f453aac..ba8b598 100644
--- a/starlarktest/assert.star
+++ b/starlarktest/assert.star
@@ -1,45 +1,45 @@
-
 # Predeclared built-ins for this module:
 #
 # error(msg): report an error in Go's test framework without halting execution.
 # catch(f): evaluate f() and returns its evaluation error message, if any
 # matches(str, pattern): report whether str matches regular expression pattern.
-# struct: a constructor for a simple HasFields implementation.
+# module(**kwargs): a constructor for a module.
 # _freeze(x): freeze the value x and everything reachable from it.
 #
 # Clients may use these functions to define their own testing abstractions.
 
 def _eq(x, y):
-  if x != y:
-    error("%r != %r" % (x, y))
+    if x != y:
+        error("%r != %r" % (x, y))
 
 def _ne(x, y):
-  if x == y:
-    error("%r == %r" % (x, y))
+    if x == y:
+        error("%r == %r" % (x, y))
 
-def _true(cond, msg="assertion failed"):
-  if not cond:
-    error(msg)
+def _true(cond, msg = "assertion failed"):
+    if not cond:
+        error(msg)
 
 def _lt(x, y):
-  if not (x < y):
-    error("%s is not less than %s" % (x, y))
+    if not (x < y):
+        error("%s is not less than %s" % (x, y))
 
 def _contains(x, y):
-  if y not in x:
-    error("%s does not contain %s" % (x, y))
+    if y not in x:
+        error("%s does not contain %s" % (x, y))
 
 def _fails(f, pattern):
-  "assert_fails asserts that evaluation of f() fails with the specified error."
-  msg = catch(f)
-  if msg == None:
-      error("evaluation succeeded unexpectedly (want error matching %r)" % pattern)
-  elif not matches(pattern, msg):
-      error("regular expression (%s) did not match error (%s)" % (pattern, msg))
+    "assert_fails asserts that evaluation of f() fails with the specified error."
+    msg = catch(f)
+    if msg == None:
+        error("evaluation succeeded unexpectedly (want error matching %r)" % pattern)
+    elif not matches(pattern, msg):
+        error("regular expression (%s) did not match error (%s)" % (pattern, msg))
 
-freeze = _freeze # an exported global whose value is the built-in freeze function
+freeze = _freeze  # an exported global whose value is the built-in freeze function
 
-assert = struct(
+assert = module(
+    "assert",
     fail = error,
     eq = _eq,
     ne = _ne,
diff --git a/starlarktest/starlarktest.go b/starlarktest/starlarktest.go
index 4cf315b..5436d22 100644
--- a/starlarktest/starlarktest.go
+++ b/starlarktest/starlarktest.go
@@ -63,7 +63,7 @@ func LoadAssertModule() (starlark.StringDict, error) {
 			"error":   starlark.NewBuiltin("error", error_),
 			"catch":   starlark.NewBuiltin("catch", catch),
 			"matches": starlark.NewBuiltin("matches", matches),
-			"struct":  starlark.NewBuiltin("struct", starlarkstruct.Make),
+			"module":  starlark.NewBuiltin("module", starlarkstruct.MakeModule),
 			"_freeze": starlark.NewBuiltin("freeze", freeze),
 		}
 		filename := DataFile("starlarktest", "assert.star")