Add initial selftests for .assignable

Comprehensive selftests are important here, because the
allno/yesconfig.py scripts only check the upper and lower bound, and
allnoconfig disables modules.

Found a bug for non-selected m-visible tristates, where n didn't show up
in sym.assignable. Everything matches menuconfig after fixing that.

Still need to test symbols in choices with different modes, imply, and
.assignable for choices.

3 files changed, 173 insertions, 2 deletions

diff --git a/kconfiglib.py b/kconfiglib.py
index 8bb8957..612fc58 100644
--- a/kconfiglib.py
+++ b/kconfiglib.py
@@ -2726,8 +2726,10 @@ class Symbol(object):
 
         # vis == 1
 
+        # Must be a tristate here, because bool m visibility gets promoted to y
+
         if not rev_dep_val:
-            return (1,) if expr_value(self.weak_rev_dep) != 2 else (2,)
+            return (0, 1) if expr_value(self.weak_rev_dep) != 2 else (0, 2)
 
         if rev_dep_val == 2:
             return (2,)
diff --git a/tests/Kassignable b/tests/Kassignable
new file mode 100644
index 0000000..97cb322
--- /dev/null
+++ b/tests/Kassignable
@@ -0,0 +1,105 @@
+config MODULES
+	bool "modules"
+	option modules
+
+
+# Things that should never be .assignable
+
+if UNDEFINED && "const"
+endif
+
+config NO_PROMPT
+
+config STRING
+	string "string"
+
+config INT
+	int "int"
+
+config HEX
+	hex "hex"
+
+
+# Non-selected symbols
+
+config Y_VIS_BOOL
+	bool "y-vis bool"
+
+config M_VIS_BOOL
+	bool "m-vis bool" if m
+
+config N_VIS_BOOL
+	bool "n-vis bool" if n
+
+config Y_VIS_TRI
+	tristate "y-vis tri"
+
+config M_VIS_TRI
+	tristate "m-vis tri" if m
+
+config N_VIS_TRI
+	tristate "n-vis tri" if n
+
+
+# Symbols selected to y
+
+config Y_SELECTOR
+	def_tristate y
+
+	select Y_SEL_Y_VIS_BOOL
+	select Y_SEL_M_VIS_BOOL
+	select Y_SEL_N_VIS_BOOL
+
+	select Y_SEL_Y_VIS_TRI
+	select Y_SEL_M_VIS_TRI
+	select Y_SEL_N_VIS_TRI
+
+config Y_SEL_Y_VIS_BOOL
+	bool "y-sel y-vis bool"
+
+config Y_SEL_M_VIS_BOOL
+	bool "y-sel m-vis bool" if m
+
+config Y_SEL_N_VIS_BOOL
+	bool "y-sel n-vis bool" if n
+
+config Y_SEL_Y_VIS_TRI
+	tristate "y-sel y-vis tri"
+
+config Y_SEL_M_VIS_TRI
+	bool "y-sel m-vis tri" if m
+
+config Y_SEL_N_VIS_TRI
+	bool "y-sel n-vis tri" if n
+
+
+# Symbols selected to m
+
+config M_SELECTOR
+	def_tristate m
+
+	select M_SEL_Y_VIS_BOOL
+	select M_SEL_M_VIS_BOOL
+	select M_SEL_N_VIS_BOOL
+
+	select M_SEL_Y_VIS_TRI
+	select M_SEL_M_VIS_TRI
+	select M_SEL_N_VIS_TRI
+
+config M_SEL_Y_VIS_BOOL
+	bool "m-sel y-vis bool"
+
+config M_SEL_M_VIS_BOOL
+	bool "m-sel m-vis bool" if m
+
+config M_SEL_N_VIS_BOOL
+	bool "m-sel n-vis bool" if n
+
+config M_SEL_Y_VIS_TRI
+	tristate "m-sel y-vis tri"
+
+config M_SEL_M_VIS_TRI
+	tristate "m-sel m-vis tri" if m
+
+config M_SEL_N_VIS_TRI
+	tristate "m-sel n-vis tri" if n
diff --git a/testsuite.py b/testsuite.py
index e750cbf..11d3ef6 100644
--- a/testsuite.py
+++ b/testsuite.py
@@ -415,7 +415,7 @@ def run_selftests():
         except KconfigSyntaxError:
             pass
         else:
-            fail('expected eval_string("{}") to throw KconfigSyntaxError, ' \
+            fail('expected eval_string("{}") to throw KconfigSyntaxError, '
                  "didn't".format(expr))
 
     # The C implementation's parser can be pretty lax about syntax. Kconfiglib
@@ -855,6 +855,70 @@ g
     assign_and_verify("HEX_m", "0x123")
 
 
+    print("Testing .assignable")
+
+    c = Kconfig("Kconfiglib/tests/Kassignable")
+
+    def verify_assignable_imp(item, assignable):
+        verify(item.assignable == assignable,
+               "Incorrect assignable values for {}. "
+               "Should be {}, was {}."
+               .format(item.name, assignable, item.assignable))
+
+        # Verify that the values can actually be assigned too
+        for val in item.assignable:
+            item.set_value(val)
+            verify(item.tri_value == val,
+                   "Unable to set {} to {}, even though "
+                   "it was in .assignable"
+                   .format(item.name, val))
+
+    def verify_assignable(sym_name, assignable):
+        verify_assignable_imp(c.syms[sym_name], assignable)
+
+    def verify_const_unassignable(sym_name):
+        verify_assignable_imp(c.const_syms[sym_name], ())
+
+    # Test with modules enabled first
+    c.modules.set_value(2)
+
+    # Things that shouldn't be .assignable
+    verify_const_unassignable("n")
+    verify_const_unassignable("m")
+    verify_const_unassignable("y")
+    verify_const_unassignable("const")
+    verify_const_unassignable("UNAME_RELEASE")
+    verify_assignable("UNDEFINED", ())
+    verify_assignable("NO_PROMPT", ())
+    verify_assignable("STRING", ())
+    verify_assignable("INT", ())
+    verify_assignable("HEX", ())
+
+    # Non-selected symbols
+    verify_assignable("Y_VIS_BOOL", (0,    2))
+    verify_assignable("M_VIS_BOOL", (0,    2))  # Visibility promoted
+    verify_assignable("N_VIS_BOOL", (       ))
+    verify_assignable("Y_VIS_TRI",  (0, 1, 2))
+    verify_assignable("M_VIS_TRI",  (0, 1   ))
+    verify_assignable("N_VIS_TRI",  (       ))
+
+    # Symbols selected to y
+    verify_assignable("Y_SEL_Y_VIS_BOOL", (2,))
+    verify_assignable("Y_SEL_M_VIS_BOOL", (2,))  # Visibility promoted
+    verify_assignable("Y_SEL_N_VIS_BOOL", (  ))
+    verify_assignable("Y_SEL_Y_VIS_TRI",  (2,))
+    verify_assignable("Y_SEL_M_VIS_TRI",  (2,))
+    verify_assignable("Y_SEL_N_VIS_TRI",  (  ))
+
+    # Symbols selected to m
+    verify_assignable("M_SEL_Y_VIS_BOOL", (   2,))  # Value promoted
+    verify_assignable("M_SEL_M_VIS_BOOL", (   2,))  # Visibility/value promoted
+    verify_assignable("M_SEL_N_VIS_BOOL", (     ))
+    verify_assignable("M_SEL_Y_VIS_TRI",  (1, 2 ))
+    verify_assignable("M_SEL_M_VIS_TRI",  (1   ,))
+    verify_assignable("M_SEL_N_VIS_TRI",  (     ))
+
+
     print("Testing object relations")
 
     c = Kconfig("Kconfiglib/tests/Krelation")