Look up the top-level Kconfig file relative to $srctree

Due to an old design braino, the top-level Kconfig filename passed to
Kconfig.__init__() wasn't looked up relative to $srctree, breaking
out-of-tree usage for e.g. menuconfig. Fixing it required ugliness like

  srctree = os.environ.get("srctree", "")
  kconfiglib.Kconfig(os.path.join(srctree, "Kconfig"))

Change the behavior of Kconfig.__init__() to look up the top-level
Kconfig file relative to $srctree. This means that all Kconfig files
(both the top-level file and any source'd files) now use $srctree, which
makes the vast majority of scripts just work when running out-of-tree.

Also remove the note re. loading a subset of Kconfig files. Saying that
the top-level file and all source'd Kconfig files are looked up relative
to $srctree should make the behavior clear enough.

Print a note about the new behavior whenever the top-level Kconfig file
can't be opened, as this change could be breaking for some scripts.

This is a slight backwards-compatiblity break, so the major version will
be bumped.

1 files changed, 8 insertions, 8 deletions

diff --git a/testsuite.py b/testsuite.py
index a521128..cddce68 100644
--- a/testsuite.py
+++ b/testsuite.py
@@ -895,17 +895,17 @@ comment "advanced comment"
 <configuration with 14 symbols, main menu prompt "Main menu", srctree is current directory, config symbol prefix "CONFIG_", warnings disabled, printing of warnings to stderr enabled, undef. symbol assignment warnings disabled, redundant symbol assignment warnings enabled>
 """)
 
-    os.environ["srctree"] = "srctree value"
+    os.environ["srctree"] = "Kconfiglib"
     os.environ["CONFIG_"] = "CONFIG_ value"
 
-    c = Kconfig("Kconfiglib/tests/Krepr", warn=False)
+    c = Kconfig("tests/Krepr", warn=False)
     c.enable_warnings()
     c.disable_stderr_warnings()
     c.disable_redun_warnings()
     c.enable_undef_warnings()
 
     verify_repr(c, """
-<configuration with 14 symbols, main menu prompt "Main menu", srctree "srctree value", config symbol prefix "CONFIG_ value", warnings enabled, printing of warnings to stderr disabled, undef. symbol assignment warnings enabled, redundant symbol assignment warnings disabled>
+<configuration with 14 symbols, main menu prompt "Main menu", srctree "Kconfiglib", config symbol prefix "CONFIG_ value", warnings enabled, printing of warnings to stderr disabled, undef. symbol assignment warnings enabled, redundant symbol assignment warnings disabled>
 """)
 
     os.environ.pop("srctree", None)
@@ -987,7 +987,7 @@ g
         os.environ["srctree"] = srctree
 
         # Has symbol with empty help text, so disable warnings
-        c = Kconfig("Kconfiglib/tests/Klocation", warn=False)
+        c = Kconfig("tests/Klocation", warn=False)
 
         verify_locations(c.syms["SINGLE_DEF"].nodes, "tests/Klocation:4")
 
@@ -1018,7 +1018,7 @@ g
         # Test recursive 'source' detection
 
         try:
-            Kconfig("Kconfiglib/tests/Krecursive1")
+            Kconfig("tests/Krecursive1")
         except KconfigError:
             pass
         except:
@@ -1030,7 +1030,7 @@ g
         # TODO: Make an exception test helper
 
         try:
-            Kconfig("Kconfiglib/tests/Kmissingsource")
+            Kconfig("tests/Kmissingsource")
         except KconfigError:
             pass
         except:
@@ -1039,7 +1039,7 @@ g
             fail("'source' with missing file did not raise exception")
 
         try:
-            Kconfig("Kconfiglib/tests/Kmissingrsource")
+            Kconfig("tests/Kmissingrsource")
         except KconfigError:
             pass
         except:
@@ -1559,7 +1559,7 @@ g
            "defconfig_filename gave wrong file with $srctree unset")
 
     os.environ["srctree"] = "Kconfiglib/tests"
-    c = Kconfig("Kconfiglib/tests/Kdefconfig_srctree")
+    c = Kconfig("Kdefconfig_srctree")
     verify(c.defconfig_filename == "Kconfiglib/tests/sub/defconfig_in_sub",
            "defconfig_filename gave wrong file with $srctree set")