Commit graph

4615 commits

Author SHA1 Message Date
Eelco Dolstra 88b44b1e94 Fix flake update check 2020-01-29 23:14:23 +01:00
Eelco Dolstra 68e0ca608f Revive the flake cache
Not that it matters a lot anymore - we respect lock files of inputs
now, so we're doing a lot fewer flake lookups.
2020-01-29 21:10:27 +01:00
Eelco Dolstra 26f895a26d Clean up the lock file handling flags
Added a flag --no-update-lock-file to barf if the lock file needs any
changes. This is useful for CI systems if you're building a
checkout. Fixes #2947.

Renamed --no-save-lock-file to --no-write-lock-file. It is now a fatal
error if the lock file needs changes but --no-write-lock-file is not
given.
2020-01-29 21:04:28 +01:00
Eelco Dolstra f68bed7f67 Add flag --override-input to override specific lock file entries
E.g.

  $ nix flake update ~/Misc/eelco-configurations/hagbard \
    --override-input 'dwarffs/nixpkgs' ../my-nixpkgs

overrides the 'nixpkgs' input of the 'dwarffs' input of the top-level
flake.

Fixes #2837.
2020-01-29 18:41:25 +01:00
Eelco Dolstra 7be1a07a45
Merge pull request #3335 from domenkozar/retry-429
retry on HTTP status code 429
2020-01-29 16:22:46 +01:00
Domen Kožar 48ddb8e481
retry on HTTP status code 429 2020-01-29 11:47:39 +01:00
Eelco Dolstra 5bbe793abf Fix --refresh with --no-net
https://hydra.nixos.org/build/110879699
2020-01-28 17:34:48 +01:00
Eelco Dolstra ab41e9d543 Merge remote-tracking branch 'origin/master' into flakes 2020-01-28 13:19:30 +01:00
Eelco Dolstra 6be04476dc Shut up warning 2020-01-28 13:16:19 +01:00
Eelco Dolstra 1af7b94c1d Add support for tarball flake inputs
For example,

  $ nix flake info https://github.com/edolstra/dwarffs/archive/master.tar.gz

Fixes #2929.
2020-01-28 13:11:02 +01:00
Eelco Dolstra c39c2503f7 Remove debug message 2020-01-27 14:28:57 +01:00
Eelco Dolstra 5046233b5a Add Mercurial tests 2020-01-27 13:45:49 +01:00
Eelco Dolstra cc22cf662b Respect lock files of inputs + fine-grained lock file control
When computing a lock file, we now respect the lock files of flake
inputs. This is important for usability / reproducibility. For
example, the 'nixops' flake depends on the 'nixops-aws' and
'nixops-hetzner' repositories. So when the 'nixops' flake is used in
another flake, we want the versions of 'nixops-aws' and
'nixops-hetzner' locked by the the 'nixops' flake because those
presumably have been tested.

This can lead to a proliferation of versions of flakes like 'nixpkgs'
(since every flake's lock file could depend on a different version of
'nixpkgs'). This is not a major issue when using Nixpkgs overlays or
NixOS modules, since then the top-level flake composes those
overlays/modules into *its* version of Nixpkgs and all other versions
are ignored. Lock file computation has been made a bit more lazy so it
won't try to fetch all those versions of 'nixpkgs'.

However, in case it's necessary to minimize flake versions, there now
are two input attributes that allow this. First, you can copy an input
from another flake, as follows:

  inputs.nixpkgs.follows = "dwarffs/nixpkgs";

This states that the calling flake's 'nixpkgs' input shall be the same
as the 'nixpkgs' input of the 'dwarffs' input.

Second, you can override inputs of inputs:

  inputs.nixpkgs.url = github:edolstra/nixpkgs/<hash>;
  inputs.nixops.inputs.nixpkgs.url = github:edolstra/nixpkgs/<hash>;

or equivalently, using 'follows':

  inputs.nixpkgs.url = github:edolstra/nixpkgs/<hash>;
  inputs.nixops.inputs.nixpkgs.follows = "nixpkgs";

This states that the 'nixpkgs' input of the 'nixops' input shall be
the same as the calling flake's 'nixpkgs' input.

Finally, at '-v' Nix now prints the changes to the lock file, e.g.

  $ nix flake update ~/Misc/eelco-configurations/hagbard
  inputs of flake 'git+file:///home/eelco/Misc/eelco-configurations?subdir=hagbard' changed:
    updated 'nixpkgs': 'github:edolstra/nixpkgs/7845bf5f4b3013df1cf036e9c9c3a55a30331db9' -> 'github:edolstra/nixpkgs/03f3def66a104a221aac8b751eeb7075374848fd'
    removed 'nixops'
    removed 'nixops/nixops-aws'
    removed 'nixops/nixops-hetzner'
    removed 'nixops/nixpkgs'
2020-01-24 22:05:11 +01:00
Eelco Dolstra 2b8ca654b0 HandleLockFile -> LockFileMode 2020-01-24 13:07:52 +01:00
Eelco Dolstra cd973fa07f Give a better error message when a flake path is not a directory 2020-01-24 13:01:34 +01:00
Robin Gloster f8dbde0813
structured-attrs: chown .attrs.* files to builder
Otherwise `chmod .`'ing the build directory doesn't work anymore, which
is done in nixpkgs if sourceRoot is set to '.'.
2020-01-23 17:38:07 +01:00
Eelco Dolstra b430a81a1f Fix coverage build
https://hydra.nixos.org/build/110757285
2020-01-22 21:58:07 +01:00
Eelco Dolstra 9a5ca802c7 clang fixes
https://hydra.nixos.org/build/110757171
2020-01-22 21:26:19 +01:00
Eelco Dolstra d506bd587a Fix clang warning 2020-01-22 21:20:01 +01:00
Eelco Dolstra 872a22fa23 resolveFlake -> lockFlake
"resolve" is ambiguous (also used for registry resolution).
2020-01-22 20:59:59 +01:00
Eelco Dolstra b5c9dbc84f Fix --override-flake and add a test 2020-01-22 20:00:58 +01:00
Eelco Dolstra 90d55ed275 Fix 'nix flake update' 2020-01-22 19:28:27 +01:00
Eelco Dolstra 32f31a8c63 nix flake info: Don't show empty descriptions 2020-01-22 17:20:21 +01:00
Eelco Dolstra b33b94748c Convert fetchMercurial to a input type
This enables Mercurial flakes. It also fixes a bug in pure mode where
you could use a branch/tag name rather than a revision.
2020-01-21 23:49:32 +01:00
Eelco Dolstra 9f4d8c6170 Pluggable fetchers
Flakes are now fetched using an extensible mechanism. Also lots of
other flake cleanups.
2020-01-21 22:56:04 +01:00
Eelco Dolstra 1bf9eb21b7 absPath(): Use std::optional 2020-01-21 22:39:43 +01:00
Eelco Dolstra 6fadb3fc03 Merge remote-tracking branch 'origin/master' into flakes 2020-01-21 21:18:52 +01:00
Eelco Dolstra aef635da78 Fix derivation computation with __structuredAttrs and multiple outputs
Fixes

  error: derivation '/nix/store/klivma7r7h5lndb99f7xxmlh5whyayvg-zlib-1.2.11.drv' has incorrect output '/nix/store/fv98nnx5ykgbq8sqabilkgkbc4169q05-zlib-1.2.11-dev', should be '/nix/store/adm7pilzlj3z5k249s8b4wv3scprhzi1-zlib-1.2.11-dev'
2020-01-21 21:14:13 +01:00
Daiderd Jordan 8b3217f832
build: remove warning when in sandboxing test mode
Introduced in 66fccd5832, but somehow
breaks the secure-drv-outputs test.
2020-01-13 22:09:18 +01:00
Eelco Dolstra c3181e21e7 Tweak error message 2020-01-13 21:52:03 +01:00
Eelco Dolstra bfaa4db7bd Merge branch 'assert-show-expression' of https://github.com/LnL7/nix 2020-01-13 21:49:55 +01:00
John Ericson d64ab5131c unbreak build without pch 2020-01-13 21:45:33 +01:00
Eelco Dolstra 835e541144 Fix build
https://hydra.nixos.org/eval/1564374
2020-01-13 21:34:54 +01:00
Daiderd Jordan 307bcb9a8e
libexpr: show expression in assertion errors
Includes the expression of the condition in the assertion message if
the assertion failed, making assertions much easier to debug. eg.

    error: assertion (withPython -> (python2Packages != null)) failed at pkgs/tools/security/nmap/default.nix:11:1
2020-01-11 15:45:41 +01:00
Yorick a350d0beb0
json-to-value: use unique_ptr instead of raw pointers 2020-01-09 22:46:41 +01:00
Yorick f1fac0b5c3
builtins.fromJSON: use nlohmann/json parser instead of custom parser 2020-01-09 17:38:27 +01:00
Nikola Knezevic 52a8f9295b Add support for \u escape in fromJSON
As fromTOML supports \u and \U escapes, bring fromJSON on par. As JSON defaults
to UTF-8 encoding (every JSON parser must support UTF-8), this change parses the
`\u hex hex hex hex` sequence (\u followed by 4 hexadecimal digits) into an
UTF-8 representation.

Add a test to verify correct parsing, using all escape sequences from json.org.
2020-01-07 00:09:58 +01:00
Nikola Knezevic cb2d348d48 Remove redundant check in parseJSONString 2020-01-07 00:09:58 +01:00
Eelco Dolstra bc22a7ee6a Fix use of uninitialized store path
Fixes 'building of '/nix/store/00000000000000000000000000000000-': ...'.
2020-01-06 22:20:10 +01:00
Eelco Dolstra e2988f48a1
Merge pull request #3303 from LnL7/darwin-sandbox
build: fix sandboxing on darwin
2020-01-06 20:56:35 +01:00
Eelco Dolstra 1dc29df1d3 Merge remote-tracking branch 'origin/master' into flakes 2020-01-06 12:43:07 +01:00
Daiderd Jordan 66fccd5832
build: fix sandboxing on darwin
Starting ba87b08f85 getEnv now returns an
std::optional which means these getEnv() != "" conditions no longer happen
if the variables are not defined.
2020-01-05 20:23:52 +01:00
Eelco Dolstra 0486e87791
Merge pull request #3302 from LnL7/darwin-repair-with-sandbox
build: fix path repairing with the darwin sandbox
2020-01-05 16:26:17 +01:00
Eelco Dolstra cb90e382b5 Hide FunctionCallTrace constructor/destructor
This prevents them from being inlined. On gcc 9, this reduces the
stack size needed for

  nix-instantiate '<nixpkgs>' -A texlive.combined.scheme-full --dry-run

from 12.9 MiB to 4.8 MiB.
2020-01-05 16:21:34 +01:00
Daiderd Jordan 7d448bc966
build: fix path repairing when hash rewriting is required
Handle store path repairing on darwin when sandboxing is enabled. Unlike
on linux sandboxing on darwin still requires hash rewriting.
2020-01-04 20:25:25 +01:00
Daiderd Jordan b33fefcb92
build: recover store path when replacing fails
This shouldn't happen in normal circumstances, but just in case
attempt to move the temporary path back if possible.
2020-01-04 20:24:27 +01:00
edef c65a6fa86a passAsFile: leave out the hash prefix
Having a colon in the path may cause issues, and having the hash
function indicated isn't actually necessary. We now verify the path 
format in the tests to prevent regressions.
2020-01-02 23:56:06 +00:00
Puck Meerburg 515c0a263e passAsFile: hash the attribute name instead of numbering sequentially
This makes the paths consistent without relying on ordering.

Co-authored-by: edef <edef@edef.eu>
2020-01-02 22:56:03 +00:00
Graham Christensen c502831a1d
exportReferencesGraph: support working
Before, we would get:

    [deploy@bastion:~]$ nix-store -r /nix/store/grfnl76cahwls0igd2by2pqv0dimi8h2-nixos-system-eris-19.09.20191213.03f3def.drv
    these derivations will be built:
      /nix/store/3ka4ihvwh6wsyhpd2qa9f59506mnxvx1-initrd-linux-4.19.88.drv
      /nix/store/ssxwmll7v21did1c8j027q0m8w6pg41i-unit-prometheus-alertmanager-irc-notifier.service.drv
      /nix/store/mvyvkj46ay7pp7b1znqbkck2mq98k0qd-unit-script-network-local-commands-start.drv
      /nix/store/vsl1y9mz38qfk6pyirjwnfzfggz5akg6-unit-network-local-commands.service.drv
      /nix/store/wi5ighfwwb83fdmav6z6n2fw6npm9ffl-unit-prometheus-hydra-exporter.service.drv
      /nix/store/x0qkv535n75pbl3xn6nn1w7qkrg9wwyg-unit-prometheus-packet-sd.service.drv
      /nix/store/lv491znsjxdf51xnfxh9ld7r1zg14d52-unit-script-packet-sd-env-key-pre-start.drv
      /nix/store/nw4nzlca49agsajvpibx7zg5b873gk9f-unit-script-packet-sd-env-key-start.drv
      /nix/store/x674wwabdwjrkhnykair4c8mpxa9532w-unit-packet-sd-env-key.service.drv
      /nix/store/ywivz64ilb1ywlv652pkixw3vxzfvgv8-unit-wireguard-wg0.service.drv
      /nix/store/v3b648293g3zl8pnn0m1345nvmyd8dwb-unit-script-acme-selfsigned-status.nixos.org-start.drv
      /nix/store/zci5d3zvr6fgdicz6k7jjka6lmx0v3g4-unit-acme-selfsigned-status.nixos.org.service.drv
      /nix/store/f6pwvnm63d0kw5df0v7sipd1rkhqxk5g-system-units.drv
      /nix/store/iax8071knxk9c7krpm9jqg0lcrawf4lc-etc.drv
      /nix/store/grfnl76cahwls0igd2by2pqv0dimi8h2-nixos-system-eris-19.09.20191213.03f3def.drv
    error: invalid file name 'closure-init-0' in 'exportReferencesGraph'

This was tough to debug, I didn't figure out which one was broken until I did:

    nix-store -r /nix/store/grfnl76cahwls0igd2by2pqv0dimi8h2-nixos-system-eris-19.09.20191213.03f3def.drv 2>&1 | grep  nix/store | xargs -n1 nix-store -r

and then looking at the remaining build graph:

    $ nix-store -r /nix/store/grfnl76cahwls0igd2by2pqv0dimi8h2-nixos-system-eris-19.09.20191213.03f3def.drv
    these derivations will be built:
      /nix/store/3ka4ihvwh6wsyhpd2qa9f59506mnxvx1-initrd-linux-4.19.88.drv
      /nix/store/grfnl76cahwls0igd2by2pqv0dimi8h2-nixos-system-eris-19.09.20191213.03f3def.drv
    error: invalid file name 'closure-init-0' in 'exportReferencesGraph'

and knowing the initrd build is before the system, then:

    $ nix show-derivation /nix/store/3ka4ihvwh6wsyhpd2qa9f59506mnxvx1-initrd-linux-4.19.88.drv
    {
      "/nix/store/3ka4ihvwh6wsyhpd2qa9f59506mnxvx1-initrd-linux-4.19.88.drv": {
        [...]
        "exportReferencesGraph": "closure-init-0 /nix/store/...-stage-1-init.sh closure-mdadm.conf-1 /nix/store/...-mdadm.conf closure-ubuntu.conf-2 ...",
        [...]
      }
    }

I then searched the repo for "in 'exportReferencesGraph'", found this
recently updated regex, and realized it was missing a "-".
2020-01-01 20:50:40 -05:00
Brian McKenna d25923263e Disable use-sqlite-wal under WSL
Before:

    $ nix-channel --update
    unpacking channels...
    warning: SQLite database '/nix/var/nix/db/db.sqlite' is busy (SQLITE_PROTOCOL)
    warning: SQLite database '/nix/var/nix/db/db.sqlite' is busy (SQLITE_PROTOCOL)
    warning: SQLite database '/nix/var/nix/db/db.sqlite' is busy (SQLITE_PROTOCOL)
    warning: SQLite database '/nix/var/nix/db/db.sqlite' is busy (SQLITE_PROTOCOL)
    warning: SQLite database '/nix/var/nix/db/db.sqlite' is busy (SQLITE_PROTOCOL)

After:

    $ inst/bin/nix-channel --update
    unpacking channels...
    created 1 symlinks in user environment

I've seen complaints that "sandbox" caused problems under WSL but I'm
having no problems. I think recent changes could have fixed the issue.
2019-12-21 08:14:19 +11:00
Eelco Dolstra c7866733d7 Merge remote-tracking branch 'origin/master' into flakes 2019-12-20 12:45:58 +01:00
Eelco Dolstra c84c843e33
tarfile.cc: Restore timestamps
This is needed to get the lastModified attribute of GitHub flakes.
2019-12-19 15:09:54 +01:00
Eelco Dolstra 2550c11373
tarfile.cc: Don't change the cwd
Nix is multithreaded so it's not safe to change the cwd.
2019-12-19 15:08:16 +01:00
Eelco Dolstra be32da0ed0
tarfile.cc: Style fixes 2019-12-19 15:01:58 +01:00
Eelco Dolstra ee235e764c
Merge branch 'libarchive' of https://github.com/yorickvP/nix 2019-12-19 14:47:18 +01:00
Eelco Dolstra 4511f09b49 nix make-content-addressable: Add --json flag
Fixes #3274.
2019-12-18 17:39:02 +01:00
Eelco Dolstra 4da1cd59ba Fix getting the timestamp of GitHub flakes 2019-12-18 17:19:30 +01:00
Eelco Dolstra 87873d0d65 Merge remote-tracking branch 'origin/master' into flakes 2019-12-18 14:25:25 +01:00
Eelco Dolstra f8abbdd456 Add priority setting to stores
This allows overriding the priority of substituters, e.g.

  $ nix-store --store ~/my-nix/ -r /nix/store/df3m4da96d84ljzxx4mygfshm1p0r2n3-geeqie-1.4 \
    --substituters 'http://cache.nixos.org?priority=100 daemon?priority=10'

Fixes #3264.
2019-12-17 17:17:53 +01:00
Eelco Dolstra ad6b738ed8 Merge remote-tracking branch 'origin/master' into flakes 2019-12-16 20:17:21 +01:00
Eelco Dolstra 54bf5ba422 nix-store -r: Handle symlinks to store paths
Fixes #3270.
2019-12-16 19:11:47 +01:00
Eelco Dolstra acb71aa5c6 Tweak error message 2019-12-15 10:44:53 +01:00
Eelco Dolstra 2b0365753a Merge branch 'limit_depth_resolveExprPath' of https://github.com/d-goldin/nix 2019-12-15 00:22:35 +01:00
Eelco Dolstra 8656a2de56
Merge pull request #3269 from xzfc/nix-shell
nix-shell: don't check for "nix-shell" in shebang script name
2019-12-14 23:24:32 +01:00
Eelco Dolstra ba6d2093c7 Fix progress bar 2019-12-14 23:19:04 +01:00
Eelco Dolstra 4947e0a91a Fix InstallableCommand 2019-12-14 23:15:36 +01:00
Eelco Dolstra b8a38fa521 Fix 'nix profile' 2019-12-14 23:09:57 +01:00
Albert Safin a70706b025 nix-shell: don't check for "nix-shell" in shebang script name 2019-12-14 15:37:20 +00:00
Eelco Dolstra ac9cc2ec08 Move some code 2019-12-13 19:10:39 +01:00
Eelco Dolstra b4edc3ca61 Don't leak exceptions 2019-12-13 19:05:26 +01:00
Eelco Dolstra e6bd88878e Improve gzip error message 2019-12-13 19:05:26 +01:00
Eelco Dolstra ca87707c90 Get rid of CBox 2019-12-13 19:05:26 +01:00
Dima d89d9958a7 bugfix: Adding depth limit to resolveExprPath
There is no termination condition for evaluation of cyclical
expression paths which can lead to infinite loops. This addresses
one spot in the parser in a similar fashion as utils.cc/canonPath
does.

This issue can be reproduced by something like:

```
ln -s a b
ln -s b a

nix-instantiate -E 'import ./a'
```
2019-12-13 14:51:30 +01:00
Eelco Dolstra e8aa2290ed Only install *.sb files on macOS 2019-12-13 14:42:55 +01:00
Eelco Dolstra 3e787423c2 Remove FIXME 2019-12-13 12:55:52 +01:00
Eelco Dolstra d1b238ec3c Simplify 2019-12-13 12:53:20 +01:00
Eelco Dolstra 2da4c61049 Merge branch 'libstore-ssh-better-exec-error-message' of https://github.com/Profpatsch/nix 2019-12-13 12:51:36 +01:00
Tom Bereknyei c6295a3afd Initial gzip support
Closes #3256
2019-12-13 03:34:15 -05:00
Profpatsch 38b29fb72c libstore/ssh: Improve error message on failing execvp
If the `throw` is reached, this means that execvp into `ssh` wasn’t
successful. We can hint at a usual problem, which is a missing `ssh`
executable.

Test with:

```
env PATH= ./result/bin/nix-copy-closure --builders '' unusedhost
```

and the bash version with

```
env PATH= ./result/bin/nix-copy-closure --builders '' localhost
```
2019-12-12 15:32:17 +01:00
Eelco Dolstra a045f93396 Temporarily revert to using 'tar' until we have gzip support 2019-12-12 15:07:31 +01:00
Eelco Dolstra ecb3a1afa2 Merge remote-tracking branch 'origin/master' into flakes 2019-12-11 14:53:30 +01:00
Eelco Dolstra bbe97dff8b Make the Store API more type-safe
Most functions now take a StorePath argument rather than a Path (which
is just an alias for std::string). The StorePath constructor ensures
that the path is syntactically correct (i.e. it looks like
<store-dir>/<base32-hash>-<name>). Similarly, functions like
buildPaths() now take a StorePathWithOutputs, rather than abusing Path
by adding a '!<outputs>' suffix.

Note that the StorePath type is implemented in Rust. This involves
some hackery to allow Rust values to be used directly in C++, via a
helper type whose destructor calls the Rust type's drop()
function. The main issue is the dynamic nature of C++ move semantics:
after we have moved a Rust value, we should not call the drop function
on the original value. So when we move a value, we set the original
value to bitwise zero, and the destructor only calls drop() if the
value is not bitwise zero. This should be sufficient for most types.

Also lots of minor cleanups to the C++ API to make it more modern
(e.g. using std::optional and std::string_view in some places).
2019-12-10 22:06:05 +01:00
Eelco Dolstra 98ef11677c EvalState::callFunction(): Make FunctionCallTrace use less stack space
The FunctionCallTrace object consumes a few hundred bytes of stack
space, even when tracing is disabled. This was causing stack overflows:

  $ nix-instantiate '<nixpkgs> -A texlive.combined.scheme-full --dry-run
  error: stack overflow (possible infinite recursion)

This is with the default stack size of 8 MiB.

Putting the object on the heap reduces stack usage to < 5 MiB.
2019-12-10 13:32:30 +01:00
Eelco Dolstra 61cc9f34d2 Remove UserLock self-lock check
This is no longer needed since we're not using POSIX locks anymore.
2019-12-09 23:57:33 +01:00
Yorick eba82b7c88
further clean up libarchive code 2019-12-09 17:21:46 +07:00
puck 28ee687adf Clean up libarchive support 2019-12-07 18:12:21 +00:00
Yorick fe7ec70e6b
remove rust unpack_tarfile ffi 2019-12-07 23:28:31 +07:00
Yorick 1355554d12
code 'cleanup' 2019-12-07 23:23:11 +07:00
Yorick f54c168031
add wrapper function around libarchive to c++ errors 2019-12-07 23:10:27 +07:00
Yorick 232b390766
fixup! libarchive proof of concept 2019-12-07 23:00:37 +07:00
Yorick 9ff5f6492f
libarchive proof of concept 2019-12-07 22:35:14 +07:00
Eelco Dolstra ab88f4bbd4 Merge remote-tracking branch 'origin/master' into flakes 2019-12-05 20:53:32 +01:00
Eelco Dolstra 3b9c9d34e5 Shut up clang warning
(cherry picked from commit 3392f1b778)
2019-12-05 20:41:44 +01:00
Eelco Dolstra 80ab95315d nix doctor: Fix typo
(cherry picked from commit 96c6b08ed7)
2019-12-05 20:40:52 +01:00
Eelco Dolstra 048ef27326 Typo 2019-12-05 20:34:34 +01:00
Eelco Dolstra 47a937d512 Show hash mismatch warnings in SRI format
(cherry picked from commit 63c5c91cc0)
2019-12-05 20:32:25 +01:00
Eelco Dolstra 0678e4d56a Move #include
(cherry picked from commit 8beedd4486)
2019-12-05 20:30:29 +01:00
Eelco Dolstra 79142cbbe1 Bindings: Add convenience method for requiring an attribute
(cherry picked from commit fb692e5f7b)
2019-12-05 20:29:15 +01:00
Eelco Dolstra 0d118ef0c9 Bindings::get(): Add convenience method
This allows writing attribute lookups as

    if (auto name = value.attrs->get(state.sName))
      ...

(cherry picked from commit f216c76c56)
2019-12-05 20:29:00 +01:00
Eelco Dolstra 5e449b43ed Initialize Command::_name
(cherry picked from commit d0a769cb06)
2019-12-05 20:21:22 +01:00