ENV_USER is intended to be used when setting any variable whose name is
controlled by the user. The names given to `function -a` certainly
qualifies. This wasn't an issue in practice because the only restriction
ENV_USER imposes is also imposed on ENV_LOCAL, but the rules may change
in the future.
This makes two changes to parse trees:
1. Unmaterialized nodes no longer have an invalid source location
For example, with the code `while false;end` there are no tokens
associated with the while loop's job_list, and therefore it is
unmaterialized. Previously it would have had a SOURCE_OFFSET_INVALID.
But now it has a zero source length, but an offset equal to the end of
the while loop (i.e. the semicolon), and a zero length. Correspondingly,
the has_source function now checks the length instead of the offset.
2. Special (comment and error) nodes have always been "disconnected,"
meaning they are not the child of any other node. However, they now have
their parent offsets set to whatever the top of the node stack was when
the node was encountered. This gives us a sense of which node the
comment is "in", e.g. if we are constructing a job list then the
comment's parent will be the job list. This lets us determine the
comment's indent.
parse_error_list_t through all of the expand functions, enabling them to
report errors more directly. Improve aspects of error reporting for
expansion failures.
Conditionally uninitialized:
- builtin_commandline.cpp:577
- expand.cpp:869
- parse_util.cpp:1036
Initialization of POD structs:
- event.cpp:61
- autoload.cpp:22
References used with va_start:
- common.cpp:608:18
Found with clang-3.4's awesome -Wconditional-uninitialized,
-Wmissing-field-initializers and -Wvarargs.
This reverts commit 74135c0600d5dcc40d396d0e7293c17b8d4bdaa7, reversing
changes made to 6d749789ce240a3e6f1447777db63fd8e7525560.
See discussion in #1317
promote it to a decoration (like 'command' or 'builtin'). This makes tab
completion and syntax highlighting treat exec's first argument as a
command and is otherwise a nice simplification. Fixes#1300
