bitbake: data: emit filename/lineno information for shell functions

Make it easier for users to debug shell task failure by including
some breadcrumbs in the emitted .run file that (hopefully) points
to the .bb/.bbclass file where the shell function was defined.

Unfortunately this won't work with functions with _append
or _prepends, since BitBake wipes the filename/lineno information.
This shouldn't be too hard to fix; for now, you'll just see
comments like this for such functions:

[YOCTO #7877]

(Bitbake rev: 9747211cbb45401cbf4dd0409e9c80c648a178c6)

Signed-off-by: Chris Laplante <chris.laplante@agilent.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 6 insertions, 0 deletions

diff --git a/bitbake/lib/bb/data.py b/bitbake/lib/bb/data.py
index b0683c5180..97022853ca 100644
--- a/bitbake/lib/bb/data.py
+++ b/bitbake/lib/bb/data.py
@@ -161,6 +161,12 @@ def emit_var(var, o=sys.__stdout__, d = init(), all=False):
         return True
 
     if func:
+        # Write a comment indicating where the shell function came from (line number and filename) to make it easier
+        # for the user to diagnose task failures. This comment is also used by build.py to determine the metadata
+        # location of shell functions.
+        o.write("# line: {0}, file: {1}\n".format(
+            d.getVarFlag(var, "lineno", False),
+            d.getVarFlag(var, "filename", False)))
         # NOTE: should probably check for unbalanced {} within the var
         val = val.rstrip('\n')
         o.write("%s() {\n%s\n}\n" % (varExpanded, val))