…uild-dependency-in

add automake as build dependency to README.md

'operator' needs to be plural here.

Users are often surprised by the requirement to parenthesize any
non-trivial object key expressions in object constructors.  E.g.,
{"a"+"b":1}.  This commit adds one more kind of key expression besides
literals and idents: variable references.

A common use case for this is jq programs as JSON templates to fill in
with variables computed from inputs or passed in on the command-line.
E.g., {some_key:$value}.  Now users can also use, e.g., {$key:$value}.

This and the restrictions on key and value expressions in object
constructors are now clarified a bit in the documentation.

Adds the release info for 1.6 to NEWS

* Set default error code to -4 in main(), Fixes jqlang#1142
* fix --exit-code with more than one object in input, Fixes jqlang#1139
    - Return code 1 or 4 based on last output, not last input.

Signed-off-by: HE, Tao <[email protected]>

"Undefined symbols are not allowed in x86_64-w64-mingw32 shared libraries"

This was also applied in the official MINGW-packages repo:
Alexpux/MINGW-packages@b5566c58a

Follow-up fix to b436156 because BOOL and DWORD
are not built-in to mingw64.

Fix grammar typo.

Replace uses of the nonstandard $^ variable by explicitly specifying the
source filenames. This is the only obvious thing preventing the build
from running correctly on non-GNU make.

my_timegm was introduced in 1900c7 to add a mktime fallback used in
4a6241, the subsequently removed in c53823. As a result of this code
shuffling, the jq mktime function (f_mktime) wound up using a fallback
even on systems where timegm is available, with incorrect results in
some time zones with DST, e.g.

% TZ=America/New_York jq -n '"2018-08-31T00:00:00Z"|fromdate|todate'
"2018-08-31T01:00:00Z"

This undoes 1900c7 and moves the workaround it added into the #else of
my_mktime.

If these values do not match exactly, it is because the UTF-8 is invalid
anyway and we counted codepoints differently than oniguruma did.  Perhaps it
would be better to error out here, but at least one similar loop already
uses < vs != and since we're off the rails anyway this might be OK.  It is
certainly better than overruning the buffer.

Resolves jqlang#1804

The distinction between input/0 and _input/0 has been unnecessary since
a9c613..7dc34b, which moved end-of-input handling into C and replaced
the jq definition of input with `def input: _input;`

The parser generates a call to error/0 on break. Having that exported
from C directly removes a language dependency on builtin.jq.

In any case, error/0 seems to be the more fundamental operation, seeing
as the old C impementation of error/1 did nothing useful with its input.

"(.+)" doesn't match new line characters so the link generated for [if-then-else](https://github.com/stedolan/jq/blob/90bc29c1b544c0436ec44246e180fdbb6d6384df/docs/content/3.manual/v1.5/manual.yml#L1804) doesn't work

Windows 10 supports color output, but it must be explicitly enabled;
ANSICON provides support for other versions.  Enable color if either of
those are available.  Resolves jqlang#1494.

Windows regards the `NUL` device as tty, which causes `WriteFile` to
fail (the bytes written pointer cannot be `NULL` in this case).  Tweak
the color test to ensure tty is accurate.

Implement `strptime` for systems lacking it, but only supporting the
ISO 8601 format string.

Windows has `_mkgmtime` for the UTC equivalent of `mktime`.

The mingw-w64 runtime expands wildcards, which causes a discrepancy
between `main`'s `argv` (multiple file names) and Windows' `wargv` (a
single wildcard).  Use `wmain` to retrieve the wide character args.

"Module path must be a string" is not a useful error message when the
reason the module path isn't a string is because the string it was got
replaced with an invalid with an error message for some other reason.

Also fixes a few memory leaks on early exits.

Only the second and subsequent path components were being checked, which
I guess is theoretically security-relevant.

There's no apparent point to reconstructing the path after splitting it
by adding /s back in, either.

The case isn't actually possible afaict.

A library marked is imported if found, but silently skipped if missing.
This is the desired semantic for the auto-include at ~/.jq

Remove the special code which loads ~/.jq in builtin.c, and instead glue
an optional include which points to the same file onto the main program
in linker.c.

Fixes a minor bug where errors in ~/.jq would be labelled <builtin>.

Avoid doing the internal binding of top-level symbols in the parser,
leaving that work to be done in a post-processing step. For builtins,
this lets us do a reference-aware bind step (block_bind_incremental)
*after* generating builtins/0.

Libraries are a bit trickier since they may be bound multiple times, so
instead of thinking through the implications I added (block_bind_self)
to resolve all internal symbols immediately.

Defaults the else clause to the identity filter "." if an else clause is
missing.

The following two jq programs are considered equivalent:

```
if .foo then
    .foo = "bar"
else
    .
end
```

```
if .foo then
    .foo = "bar"
end
```

Stop losing \0s from the end of files because we don't know how much
fgets() read into our buffer. If we prefill the buffer with anything
other than zeroes, we can actually tell the difference between the
terminator and unused space in the buffer.

This is possibly more expensive, but at least it should be correct.

Fixes jqlang#1504

Since 605bfb3, block_drop_unreferenced actually reverses the order of
instructions in the block it's run against. This bug was hidden by the
fact that normally it's run *twice* against the main program, flipping
it back, and that order of function definitionss doesn't really matter
after symbol resolution.

block_bind_incremental is block_bind_referenced in a loop backwards. For
an 1-inst block, it does the same thing and isn't too much more
expensive, so it's not really useful to keep both.

Also, block_bind_referenced was a better name for the function.

(The correctness of this change is more obvious after the rename.)

Fixes the bug where all and any evaluate one more item than needed.

New implementation in terms of while/2, and branches immediately on $by
to avoid checking the sign of $by *in* the loop.

(`path(.[])` is a streaming `keys`!)

The behavior of memmem for an empty needle is inconsistent between
implementations of libc.
Our tests imply that we want an empty string needle to be true,
so check for an empty needle before calling memmem.

Temporarily(?) make tests/shtest verbose to help diagnose Travis alpine
build failures.

Count arguments up-front at definition/invocation instead of doing it at
bind time, which comes after generating builtins/0 since e843a4f.

However, we should really use the argv[0] progname, not just jq.
Someday we may want to support aliases which automatically add certain
options, etc.

Expressions of the form `path(EXPR) | select(GENERATOR)`, where `EXPR`
is a path expression and `GENERATOR` is a generator conditional
expression (e.g., `has("a"), has("b")`) cause an assertion if the
jq_state VM is torn down too soon.  That assert() was only correct if
assuming that the conditional is not a generator.

If the conditional is generator, then what we see is that when
backtracking a SUBEXP_END is executed without a corresponding
SUBEXP_BEGIN because the entire conditional is bracketed with
SUBEXP_BEGIN and SUBEXP_END, and since it's resumed in the middle, in
between the brackets.

Rather than assert that the jq->path_len being restored has some
particular value, we can simply re-compute it from the restored
jq->path.

pkg-config is a common interface to resolve build details. It will
become easier to incorporate libjq in other projects by providing this
interface.

Configure the environment to inform debconf that it's running in
noninteractive mode, to avoid some warnings.

Avoid RuntimeError in pipenv by setting LC_ALL and LANG to C.UTF-8.

Fetch oniguruma using git submodule instead of a release tarball. It
will fix a build problem, caused by jq's autotools configuration, trying
to run `make distclean` recursively in an empty modules directory. This
will also improve the maintainability of the Dockerfile.

Run `make uninstall` for oniguruma before running the recursive
distclean that will remove oniguruma's Makefile and cause a build error
due to missing make target.

Calloc will zero the allocated memory which makes one memset and a
number of explicit zero assignments redundant.

The current paragraph is not complete, since a digit is not a special character.

Changing it to:

    If the key contains special characters or starts with a digit,
    you need to surround it with double quotes like this:
    `."foo$"`, or else `.["foo$"]`.

clarify filter usage

The current instructions tell users to perform two actions:
- update the package database
- install the jq package

The only thing users need to or should be doing is actually installing
the jq package -- regardless of which version is being installed.
Guidelines on how to perform system updates are massively out of scope.

In the case of partially performing a system update as a prerequisite
for installing jq, the official guidance from Arch Linux is not to do
this: partial updates are not supported, we refuse to support them, and
anyone who does try to perform them anyway is assumed to know so much
about their system that they clearly do not ever need help from anyone
else (which is a good thing since they won't get it). The result is a
frankensteined system that can only ever be supported by the person who
frankensteined it to begin with. The only reason the package manager
even allows it to occur in the first place is because other
distributions using pacman might have different LTS policies, and
because it would prevent expert users from being in control of their
system, as per the traditional Unix philosophy:

"Unix was not designed to stop you from doing stupid things, because
that would also stop you from doing clever things."

Consequences of performing partial updates without understanding the
ramifications in extensive detail can include breaking the partially
updated application (jq), breaking any application that shares a mutual
dependency with the partially updated application (which jq is *lucky*
to only depend on the ever-backwards-compatible glibc), or breaking the
entire operating system by leaving armed traps behind for the next time
a `pacman -S new-package` is executed and thereby breaks *its* cascading
dependencies.

See:
https://wiki.archlinux.org/index.php/System_maintenance#Partial_upgrades_are_unsupported

docs: fix seriously dangerous download instructions for Arch Linux

The library adds support for decimal numbers of arbitrary length.
Downloaded from ICU, under ICU 1.8.1 license
http://download.icu-project.org/files/decNumber/decNumber-icu-368.zip