When reporting an error to the user, add information about the offending
object/value (possibly truncated).
The goal is to give a user some context regarding which input object
caused the runtime error.
Examples:
$ echo '"hello"' | ./jq '-.'
jq: error: string ("hello") cannot be negated
$ echo '"very-long-string"' | ./jq '-.'
jq: error: string ("very-long-...) cannot be negated
$ echo '["1",2]' | ./jq '.|join(",")'
jq: error: string (",") and number (2) cannot be added
$ echo '["1","2",{"a":{"b":{"c":33}}}]' | ./jq '.|join(",")'
jq: error: string (",") and object ({"a":{"b":{...) cannot be added
$ echo '{"a":{"b":{"c":33}}}' | ./jq '.a | @tsv'
jq: error: object ({"b":{"c":33}}) cannot be tsv-formatted, only array
(Fix#754)
With this patch, jq run-time errors printed to stderr will contain the
filename and line of the offending input.
But note that the JSON text parser does (yet) print the input filename
on parse error. A jq run-time error is a jq program error, not
including syntax errors nor JSON text input format errors.
Examples:
With stdin and multiple lines:
$ printf '{"a":43}\n{"a":{"b":66}}\n' | ./jq '.a+1'
44
jq: error (at stdin:2): object and number cannot be added
With multiple files:
$ printf '{"a":43}' > 1.json
$ printf '{"a":"hello"}\n' > 2.json
$ printf '{"a":{"b":66}}\n' > 3.json
$ ./jq '[.a]|@tsv' 1.json 2.json 3.json
"43"
"hello"
jq: error (at 3.json:1): object is not valid in a csv row
With very long lines (spanning multiple `fgets` calls):
$ ( printf '{"a":43}\n' ;
printf '{"a":{"b":[' ; seq 10000 | paste -d, -s | tr -d '\n' ;
printf ']}}\n' ;
printf '{"a":"hello"}\n' ) | ./jq '[.a] | @tsv'
"43"
jq: error (at stdin:2): object is not valid in a csv row
"hello"
With raw input:
$ seq 1000 | ./jq --raw-input 'select(.=="700") | . + 10'
jq: error (at stdin:700): string and number cannot be added
Caveat:
The reported line will be the last line of the (valid) parsed JSON data.
Example:
$ printf '{\n"a":\n"hello"\n\n\n}\n' | ./jq '.a+4'
jq: error (at stdin:6): string and number cannot be added
We can't know how many bytes fgets() read when we reach EOF and fgets()
didn't see a newline; we can only assume that at least strlen(buf) bytes
were read. This is quite obnoxious if one wants to use NULs in raw
input, but at least we can make reading "a\0b\0c\0" with no newline
yield "a\0b\0c", losing only the final sequence of NULs.
We can't use getline() either, since it will want to allocate a buffer
big enough for an entire line, and we might not have any newlines in our
input. A complete fix will have to use getc() or read(), preferably the
latter.
When trying to use the new regex functions (match/test/sub/capture/etc)
in a JQ that was compiled without the ONIGURAMA regex library,
report an informative error message instead of a 'not defined' error.
Before:
$ echo '"foo"' | ./jq-old 'test("foo")'
jq: error: test/1 is not defined at <top-level>, line 1:
test("foo")
jq: 1 compile error
After:
$ echo '"foo"' | ./jq 'test("foo")'
jq: error: jq was compiled without ONIGURAMA regex libary. match/test/sub and related functions are not available.
When running `make` I ran into a couple of problems building the manual. While
I'm not entirely sure that this is the root cause, it appears to have been
related to the fact that ruby 2.0 dropped syck completely in favor of psych
(which was introduced in 1.9.2) for YAML processing. I'm currently using ruby
2.1.0p0.
I'm assuming that the fact that the YAML engine was explicitly set to syck in
the Rakefile was an attempt to work around some incompatibility between the two
libraries, so I looked into what would be necessary to get it to work with the
newer one. The changes to `manual.yml` ended up being pretty minor: I ran it
through `iconv` to convert some ISO-8859-1 characters to UTF-8 and added some
quotes in places (apparently you can't start a string value with '`').
When escaping string (e.g. for `@tsv` or `@csv` outputs),
escape NULs as '\0'.
Existing behaviour, unchanged by this patch:
$ echo '"a\u0000b"' | ./jq '.'
"a\u0000b"
$ echo '"a\u0000b"' | ./jq -r '.' | od -a
0000000 a nul b nl
0000004
When using `@tsv`, escape NUL to `\0`:
$ echo '"a\u0000b"' | ./jq -r '[.]|@tsv'
a\0b
$ echo '"a\u0000b"' | ./jq '[.]|@tsv'
"a\\0b"
Nicolas Williams