Merge "Add repl-overlays" into main
This commit is contained in:
Gerrit Code Review
commit
a95c62673b
36
doc/manual/rl-next/repl-overlays.md
Normal file
36
doc/manual/rl-next/repl-overlays.md
Normal file
|
|
@ -0,0 +1,36 @@
|
|||
---
|
||||
synopsis: Add `repl-overlays` option
|
||||
prs: 10203
|
||||
cls: 504
|
||||
---
|
||||
|
||||
A `repl-overlays` option has been added, which specifies files that can overlay
|
||||
and modify the top-level bindings in `nix repl`. For example, with the
|
||||
following contents in `~/.config/nix/repl.nix`:
|
||||
|
||||
```nix
|
||||
info: final: prev: let
|
||||
optionalAttrs = predicate: attrs:
|
||||
if predicate
|
||||
then attrs
|
||||
else {};
|
||||
in
|
||||
optionalAttrs (prev ? legacyPackages && prev.legacyPackages ? ${info.currentSystem})
|
||||
{
|
||||
pkgs = prev.legacyPackages.${info.currentSystem};
|
||||
}
|
||||
```
|
||||
|
||||
We can run `nix repl` and use `pkgs` to refer to `legacyPackages.${currentSystem}`:
|
||||
|
||||
```ShellSession
|
||||
$ nix repl --repl-overlays ~/.config/nix/repl.nix nixpkgs
|
||||
Lix 2.90.0
|
||||
Type :? for help.
|
||||
Loading installable 'flake:nixpkgs#'...
|
||||
Added 5 variables.
|
||||
Loading 'repl-overlays'...
|
||||
Added 6 variables.
|
||||
nix-repl> pkgs.bash
|
||||
«derivation /nix/store/g08b5vkwwh0j8ic9rkmd8mpj878rk62z-bash-5.2p26.drv»
|
||||
```
|
||||
|
|
@ -13,3 +13,5 @@ libcmd_LDFLAGS = $(EDITLINE_LIBS) $(LOWDOWN_LIBS) $(NIXDOC_LIBS) -pthread
|
|||
libcmd_LIBS = libstore libutil libexpr libmain libfetchers
|
||||
|
||||
$(eval $(call install-file-in, $(buildprefix)$(d)/nix-cmd.pc, $(libdir)/pkgconfig, 0644))
|
||||
|
||||
$(d)/repl.cc: $(d)/repl-overlays.nix.gen.hh
|
||||
|
|
|
|||
|
|
@ -32,8 +32,13 @@ libcmd_headers = files(
|
|||
'repl.hh',
|
||||
)
|
||||
|
||||
libcmd_generated_headers = [
|
||||
gen_header.process('repl-overlays.nix', preserve_path_from: meson.current_source_dir()),
|
||||
]
|
||||
|
||||
libcmd = library(
|
||||
'nixcmd',
|
||||
libcmd_generated_headers,
|
||||
libcmd_sources,
|
||||
dependencies : [
|
||||
liblixutil,
|
||||
|
|
|
|||
8
src/libcmd/repl-overlays.nix
Normal file
8
src/libcmd/repl-overlays.nix
Normal file
|
|
@ -0,0 +1,8 @@
|
|||
info:
|
||||
initial:
|
||||
functions:
|
||||
let final = builtins.foldl'
|
||||
(prev: function: prev // (function info final prev))
|
||||
initial
|
||||
functions;
|
||||
in final
|
||||
|
|
@ -30,6 +30,7 @@
|
|||
#include "signals.hh"
|
||||
#include "print.hh"
|
||||
#include "progress-bar.hh"
|
||||
#include "gc-small-vector.hh"
|
||||
|
||||
#if HAVE_BOEHMGC
|
||||
#define GC_INCLUDE_NEW
|
||||
|
|
@ -118,6 +119,45 @@ struct NixRepl
|
|||
void evalString(std::string s, Value & v);
|
||||
void loadDebugTraceEnv(DebugTrace & dt);
|
||||
|
||||
/**
|
||||
* Load the `repl-overlays` and add the resulting AttrSet to the top-level
|
||||
* bindings.
|
||||
*/
|
||||
void loadReplOverlays();
|
||||
|
||||
/**
|
||||
* Get a list of each of the `repl-overlays` (parsed and evaluated).
|
||||
*/
|
||||
Value * replOverlays();
|
||||
|
||||
/**
|
||||
* Get the Nix function that composes the `repl-overlays` together.
|
||||
*/
|
||||
Value * getReplOverlaysEvalFunction();
|
||||
|
||||
/**
|
||||
* Cached return value of `getReplOverlaysEvalFunction`.
|
||||
*
|
||||
* Note: This is `shared_ptr` to avoid garbage collection.
|
||||
*/
|
||||
std::shared_ptr<Value *> replOverlaysEvalFunction =
|
||||
std::allocate_shared<Value *>(traceable_allocator<Value *>(), nullptr);
|
||||
|
||||
/**
|
||||
* Get the `info` AttrSet that's passed as the first argument to each
|
||||
* of the `repl-overlays`.
|
||||
*/
|
||||
Value * replInitInfo();
|
||||
|
||||
/**
|
||||
* Get the current top-level bindings as an AttrSet.
|
||||
*/
|
||||
Value * bindingsToAttrs();
|
||||
/**
|
||||
* Parse a file, evaluate its result, and force the resulting value.
|
||||
*/
|
||||
Value * evalFile(SourcePath & path);
|
||||
|
||||
void printValue(std::ostream & str,
|
||||
Value & v,
|
||||
unsigned int maxDepth = std::numeric_limits<unsigned int>::max())
|
||||
|
|
@ -770,14 +810,114 @@ void NixRepl::loadFiles()
|
|||
loadedFiles.clear();
|
||||
|
||||
for (auto & i : old) {
|
||||
notice("Loading '%1%'...", i);
|
||||
notice("Loading '%1%'...", Magenta(i));
|
||||
loadFile(i);
|
||||
}
|
||||
|
||||
for (auto & [i, what] : getValues()) {
|
||||
notice("Loading installable '%1%'...", what);
|
||||
notice("Loading installable '%1%'...", Magenta(what));
|
||||
addAttrsToScope(*i);
|
||||
}
|
||||
|
||||
loadReplOverlays();
|
||||
}
|
||||
|
||||
void NixRepl::loadReplOverlays()
|
||||
{
|
||||
if (!evalSettings.replOverlays) {
|
||||
return;
|
||||
}
|
||||
|
||||
notice("Loading '%1%'...", Magenta("repl-overlays"));
|
||||
auto replInitFilesFunction = getReplOverlaysEvalFunction();
|
||||
|
||||
Value &newAttrs(*state->allocValue());
|
||||
SmallValueVector<3> args = {replInitInfo(), bindingsToAttrs(), replOverlays()};
|
||||
state->callFunction(
|
||||
*replInitFilesFunction,
|
||||
args.size(),
|
||||
args.data(),
|
||||
newAttrs,
|
||||
replInitFilesFunction->determinePos(noPos)
|
||||
);
|
||||
|
||||
addAttrsToScope(newAttrs);
|
||||
}
|
||||
|
||||
Value * NixRepl::getReplOverlaysEvalFunction()
|
||||
{
|
||||
if (replOverlaysEvalFunction && *replOverlaysEvalFunction) {
|
||||
return *replOverlaysEvalFunction;
|
||||
}
|
||||
|
||||
auto evalReplInitFilesPath = CanonPath::root + "repl-overlays.nix";
|
||||
*replOverlaysEvalFunction = state->allocValue();
|
||||
auto code =
|
||||
#include "repl-overlays.nix.gen.hh"
|
||||
;
|
||||
auto expr = state->parseExprFromString(
|
||||
code,
|
||||
SourcePath(evalReplInitFilesPath),
|
||||
state->staticBaseEnv
|
||||
);
|
||||
|
||||
state->eval(expr, **replOverlaysEvalFunction);
|
||||
|
||||
return *replOverlaysEvalFunction;
|
||||
}
|
||||
|
||||
Value * NixRepl::replOverlays()
|
||||
{
|
||||
Value * replInits(state->allocValue());
|
||||
state->mkList(*replInits, evalSettings.replOverlays.get().size());
|
||||
Value ** replInitElems = replInits->listElems();
|
||||
|
||||
size_t i = 0;
|
||||
for (auto path : evalSettings.replOverlays.get()) {
|
||||
debug("Loading '%1%' path '%2%'...", "repl-overlays", path);
|
||||
SourcePath sourcePath((CanonPath(path)));
|
||||
auto replInit = evalFile(sourcePath);
|
||||
|
||||
if (!replInit->isLambda()) {
|
||||
state->error<TypeError>(
|
||||
"Expected `repl-overlays` to be a lambda but found %1%: %2%",
|
||||
showType(*replInit),
|
||||
ValuePrinter(*state, *replInit, errorPrintOptions)
|
||||
)
|
||||
.atPos(replInit->determinePos(noPos))
|
||||
.debugThrow();
|
||||
}
|
||||
|
||||
if (replInit->lambda.fun->hasFormals()
|
||||
&& !replInit->lambda.fun->formals->ellipsis) {
|
||||
state->error<TypeError>(
|
||||
"Expected first argument of %1% to have %2% to allow future versions of Lix to add additional attributes to the argument",
|
||||
"repl-overlays",
|
||||
"..."
|
||||
)
|
||||
.atPos(replInit->determinePos(noPos))
|
||||
.debugThrow();
|
||||
}
|
||||
|
||||
replInitElems[i] = replInit;
|
||||
i++;
|
||||
}
|
||||
|
||||
|
||||
return replInits;
|
||||
}
|
||||
|
||||
Value * NixRepl::replInitInfo()
|
||||
{
|
||||
auto builder = state->buildBindings(2);
|
||||
|
||||
Value * currentSystem(state->allocValue());
|
||||
currentSystem->mkString(evalSettings.getCurrentSystem());
|
||||
builder.insert(state->symbols.create("currentSystem"), currentSystem);
|
||||
|
||||
Value * info(state->allocValue());
|
||||
info->mkAttrs(builder.finish());
|
||||
return info;
|
||||
}
|
||||
|
||||
|
||||
|
|
@ -810,6 +950,18 @@ void NixRepl::addVarToScope(const Symbol name, Value & v)
|
|||
varNames.emplace(state->symbols[name]);
|
||||
}
|
||||
|
||||
Value * NixRepl::bindingsToAttrs()
|
||||
{
|
||||
auto builder = state->buildBindings(staticEnv->vars.size());
|
||||
for (auto & [symbol, displacement] : staticEnv->vars) {
|
||||
builder.insert(symbol, env->values[displacement]);
|
||||
}
|
||||
|
||||
Value * attrs(state->allocValue());
|
||||
attrs->mkAttrs(builder.finish());
|
||||
return attrs;
|
||||
}
|
||||
|
||||
|
||||
Expr * NixRepl::parseString(std::string s)
|
||||
{
|
||||
|
|
@ -824,6 +976,15 @@ void NixRepl::evalString(std::string s, Value & v)
|
|||
state->forceValue(v, v.determinePos(noPos));
|
||||
}
|
||||
|
||||
Value * NixRepl::evalFile(SourcePath & path)
|
||||
{
|
||||
auto expr = state->parseExprFromFile(path, staticEnv);
|
||||
Value * result(state->allocValue());
|
||||
expr->eval(*state, *env, *result);
|
||||
state->forceValue(*result, result->determinePos(noPos));
|
||||
return result;
|
||||
}
|
||||
|
||||
|
||||
std::unique_ptr<AbstractNixRepl> AbstractNixRepl::create(
|
||||
const SearchPath & searchPath, nix::ref<Store> store, ref<EvalState> state,
|
||||
|
|
|
|||
|
|
@ -125,6 +125,42 @@ struct EvalSettings : Config
|
|||
|
||||
This is useful for debugging warnings in third-party Nix code.
|
||||
)"};
|
||||
|
||||
PathsSetting replOverlays{this, Paths(), "repl-overlays",
|
||||
R"(
|
||||
A list of files containing Nix expressions that can be used to add
|
||||
default bindings to [`nix
|
||||
repl`](@docroot@/command-ref/new-cli/nix3-repl.md) sessions.
|
||||
|
||||
Each file is called with three arguments:
|
||||
1. An [attribute set](@docroot@/language/values.html#attribute-set)
|
||||
containing at least a
|
||||
[`currentSystem`](@docroot@/language/builtin-constants.md#builtins-currentSystem)
|
||||
attribute (this is identical to
|
||||
[`builtins.currentSystem`](@docroot@/language/builtin-constants.md#builtins-currentSystem),
|
||||
except that it's available in
|
||||
[`pure-eval`](@docroot@/command-ref/conf-file.html#conf-pure-eval)
|
||||
mode).
|
||||
2. The top-level bindings produced by the previous `repl-overlays`
|
||||
value (or the default top-level bindings).
|
||||
3. The final top-level bindings produced by calling all
|
||||
`repl-overlays`.
|
||||
|
||||
For example, the following file would alias `pkgs` to
|
||||
`legacyPackages.${info.currentSystem}` (if that attribute is defined):
|
||||
|
||||
```nix
|
||||
info: final: prev:
|
||||
if prev ? legacyPackages
|
||||
&& prev.legacyPackages ? ${info.currentSystem}
|
||||
then
|
||||
{
|
||||
pkgs = prev.legacyPackages.${info.currentSystem};
|
||||
}
|
||||
else
|
||||
{ }
|
||||
```
|
||||
)"};
|
||||
};
|
||||
|
||||
extern EvalSettings evalSettings;
|
||||
|
|
|
|||
|
|
@ -0,0 +1 @@
|
|||
info: final: prev: builtins.abort "uh oh!"
|
||||
|
|
@ -0,0 +1,6 @@
|
|||
let
|
||||
puppy = "doggy";
|
||||
in
|
||||
{currentSystem}: final: prev: {
|
||||
inherit puppy;
|
||||
}
|
||||
|
|
@ -0,0 +1 @@
|
|||
info: final: prev: {}
|
||||
|
|
@ -0,0 +1,4 @@
|
|||
info: final: prev:
|
||||
{
|
||||
pkgs = final.packages.x86_64-linux;
|
||||
}
|
||||
|
|
@ -0,0 +1,7 @@
|
|||
info: final: prev:
|
||||
{
|
||||
var = prev.var + "b";
|
||||
|
||||
# We can access the final value of `var` here even though it isn't defined yet:
|
||||
varUsingFinal = "final value is: " + final.newVar;
|
||||
}
|
||||
|
|
@ -0,0 +1,6 @@
|
|||
info: final: prev:
|
||||
{
|
||||
var = prev.var + "c";
|
||||
|
||||
newVar = "puppy";
|
||||
}
|
||||
|
|
@ -0,0 +1,3 @@
|
|||
{
|
||||
packages.x86_64-linux.default = "my package";
|
||||
}
|
||||
|
|
@ -0,0 +1,5 @@
|
|||
Check basic `repl-overlays` functionality.
|
||||
@args --repl-overlays
|
||||
@args ${PWD}/extra_data/repl-overlay-packages-is-pkgs.nix
|
||||
nix-repl> pkgs
|
||||
{ default = "my package"; }
|
||||
|
|
@ -0,0 +1,3 @@
|
|||
{
|
||||
var = "a";
|
||||
}
|
||||
|
|
@ -0,0 +1,7 @@
|
|||
Check that multiple `repl-overlays` can compose together
|
||||
@args --repl-overlays
|
||||
@args "${PWD}/extra_data/repl-overlays-compose-1.nix ${PWD}/extra_data/repl-overlays-compose-2.nix"
|
||||
nix-repl> var
|
||||
"abc"
|
||||
nix-repl> varUsingFinal
|
||||
"final value is: puppy"
|
||||
|
|
@ -0,0 +1,10 @@
|
|||
`repl-overlays` that try to parse out the `info` argument without a `...` error.
|
||||
@args --repl-overlays
|
||||
@args ${PWD}/extra_data/repl-overlay-no-dotdotdot.nix
|
||||
@should-start false
|
||||
error: Expected first argument of repl-overlays to have ... to allow future versions of Lix to add additional attributes to the argument
|
||||
at $TEST_DATA/extra_data/repl-overlay-no-dotdotdot.nix:4:3:
|
||||
3| in
|
||||
4| {currentSystem}: final: prev: {
|
||||
| ^
|
||||
5| inherit puppy;\n
|
||||
|
|
@ -0,0 +1,5 @@
|
|||
`repl-overlays` that don't destructure the `info` argument are OK.
|
||||
@args --repl-overlays
|
||||
@args ${PWD}/extra_data/repl-overlay-no-formals.nix
|
||||
nix-repl> 1
|
||||
1
|
||||
|
|
@ -0,0 +1,22 @@
|
|||
`repl-overlays` that fail to evaluate should error.
|
||||
@args --repl-overlays
|
||||
@args ${PWD}/extra_data/repl-overlay-fail.nix
|
||||
@should-start false
|
||||
error:
|
||||
… while calling the 'foldl'' builtin
|
||||
at «string»:5:13:
|
||||
4| functions:
|
||||
5| let final = builtins.foldl'
|
||||
| ^
|
||||
6| (prev: function: prev // (function info final prev))
|
||||
|
||||
… in the right operand of the update (//) operator
|
||||
at «string»:6:37:
|
||||
5| let final = builtins.foldl'
|
||||
6| (prev: function: prev // (function info final prev))
|
||||
| ^
|
||||
7| initial
|
||||
|
||||
(stack trace truncated; use '--show-trace' to show the full trace)
|
||||
|
||||
error: evaluation aborted with the following error message: 'uh oh!'
|
||||
|
|
@ -0,0 +1 @@
|
|||
info: final: prev: builtins.abort "uh oh!"
|
||||
|
|
@ -0,0 +1 @@
|
|||
{currentSystem}: final: prev: {}
|
||||
|
|
@ -0,0 +1,4 @@
|
|||
info: final: prev:
|
||||
{
|
||||
pkgs = final.packages.x86_64-linux;
|
||||
}
|
||||
|
|
@ -0,0 +1,7 @@
|
|||
info: final: prev:
|
||||
{
|
||||
var = prev.var + "b";
|
||||
|
||||
# We can access the final value of `var` here even though it isn't defined yet:
|
||||
varUsingFinal = "final value is: " + final.newVar;
|
||||
}
|
||||
|
|
@ -0,0 +1,6 @@
|
|||
info: final: prev:
|
||||
{
|
||||
var = prev.var + "c";
|
||||
|
||||
newVar = "puppy";
|
||||
}
|
||||
|
|
@ -179,7 +179,12 @@ REPL_TEST(no_nested_debuggers);
|
|||
REPL_TEST(regression_9917);
|
||||
REPL_TEST(regression_9918);
|
||||
REPL_TEST(regression_l145);
|
||||
REPL_TEST(stack_vars);
|
||||
REPL_TEST(repl_overlays);
|
||||
REPL_TEST(repl_overlays_compose);
|
||||
REPL_TEST(repl_overlays_destructure_without_dotdotdot_errors);
|
||||
REPL_TEST(repl_overlays_destructure_without_formals_ok);
|
||||
REPL_TEST(repl_overlays_error);
|
||||
REPL_TEST(repl_printing);
|
||||
REPL_TEST(stack_vars);
|
||||
|
||||
}; // namespace nix
|
||||
|
|
|
|||
Loading…
Reference in a new issue