bitbake: ast: Add error when trying to use dash in sh function names

A dash character is illegal in function names in sh (but not bash). Since
our shell tasks run under sh and the shell parser is sh based, EXPORT_FUNCTIONS
won't work with class names containing a dash.

We can't change sh, we can ensure the user is warned about the problem
straight away though.

[YOCTO #7006]

(Bitbake rev: 86704281b79e524dccccc88cbf996b299b33bae2)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/bb/parse/ast.py

@@ -226,6 +226,8 @@ class ExportFuncsNode(AstNode):
             if data.getVarFlag(calledfunc, "python"):
                 data.setVar(func, "    bb.build.exec_func('" + calledfunc + "', d)\n")
             else:
+                if "-" in self.classname:
+                   bb.fatal("The classname %s contains a dash character and is calling an sh function %s using EXPORT_FUNCTIONS. Since a dash is illegal in sh function names, this cannot work, please rename the class or don't use EXPORT_FUNCTIONS." % (self.classname, calledfunc))
                 data.setVar(func, "    " + calledfunc + "\n")
             data.setVarFlag(func, 'export_func', '1')