Merge pull request #196251 from hercules-ci/testers-build-failure-and-equal-contents

`testers`: Add `testBuildFailure` and `testEqualContents`

Changed files
+343 -2
doc
pkgs
build-support
+64
doc/builders/testers.chapter.md
···
};
```
+
## `testBuildFailure` {#tester-testBuildFailure}
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+
Make sure that a build does not succeed. This is useful for testing testers.
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This returns a derivation with an override on the builder, with the following effects:
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- Fail the build when the original builder succeeds
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- Move `$out` to `$out/result`, if it exists (assuming `out` is the default output)
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- Save the build log to `$out/testBuildFailure.log` (same)
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+
Example:
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```nix
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runCommand "example" {
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failed = testers.testBuildFailure (runCommand "fail" {} ''
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echo ok-ish >$out
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echo failing though
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exit 3
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'');
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} ''
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grep -F 'ok-ish' $failed/result
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grep -F 'failing though' $failed/testBuildFailure.log
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[[ 3 = $(cat $failed/testBuildFailure.exit) ]]
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touch $out
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'';
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```
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While `testBuildFailure` is designed to keep changes to the original builder's
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environment to a minimum, some small changes are inevitable.
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- The file `$TMPDIR/testBuildFailure.log` is present. It should not be deleted.
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- `stdout` and `stderr` are a pipe instead of a tty. This could be improved.
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- One or two extra processes are present in the sandbox during the original
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builder's execution.
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- The derivation and output hashes are different, but not unusual.
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- The derivation includes a dependency on `buildPackages.bash` and
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`expect-failure.sh`, which is built to include a transitive dependency on
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`buildPackages.coreutils` and possibly more. These are not added to `PATH`
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or any other environment variable, so they should be hard to observe.
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## `testEqualContents` {#tester-equalContents}
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Check that two paths have the same contents.
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Example:
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```nix
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testers.testEqualContents {
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assertion = "sed -e performs replacement";
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expected = writeText "expected" ''
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foo baz baz
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'';
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actual = runCommand "actual" {
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# not really necessary for a package that's in stdenv
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nativeBuildInputs = [ gnused ];
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base = writeText "base" ''
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foo bar baz
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'';
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} ''
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sed -e 's/bar/baz/g' $base >$out
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'';
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}
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```
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## `testEqualDerivation` {#tester-testEqualDerivation}
Checks that two packages produce the exact same build instructions.
+53 -1
pkgs/build-support/testers/default.nix
···
-
{ pkgs, lib, callPackage, runCommand, stdenv }:
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{ pkgs, buildPackages, lib, callPackage, runCommand, stdenv, substituteAll, }:
# Documentation is in doc/builders/testers.chapter.md
{
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# See https://nixos.org/manual/nixpkgs/unstable/#tester-testBuildFailure
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# or doc/builders/testers.chapter.md
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testBuildFailure = drv: drv.overrideAttrs (orig: {
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builder = buildPackages.bash;
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args = [
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(substituteAll { coreutils = buildPackages.coreutils; src = ./expect-failure.sh; })
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orig.realBuilder or stdenv.shell
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] ++ orig.args or ["-e" (orig.builder or ../../stdenv/generic/default-builder.sh)];
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});
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# See https://nixos.org/manual/nixpkgs/unstable/#tester-testEqualDerivation
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# or doc/builders/testers.chapter.md
testEqualDerivation = callPackage ./test-equal-derivation.nix { };
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# See https://nixos.org/manual/nixpkgs/unstable/#tester-testEqualContents
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# or doc/builders/testers.chapter.md
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testEqualContents = {
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assertion,
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actual,
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expected,
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}: runCommand "equal-contents-${lib.strings.toLower assertion}" {
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inherit assertion actual expected;
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} ''
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echo "Checking:"
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echo "$assertion"
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if ! diff -U5 -r "$actual" "$expected" --color=always
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then
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echo
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echo 'Contents must be equal, but were not!'
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echo
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echo "+: expected, at $expected"
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echo "-: unexpected, at $actual"
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exit 1
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else
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find "$expected" -type f -executable > expected-executables | sort
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find "$actual" -type f -executable > actual-executables | sort
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if ! diff -U0 actual-executables expected-executables --color=always
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then
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echo
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echo "Contents must be equal, but some files' executable bits don't match"
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echo
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echo "+: make this file executable in the actual contents"
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echo "-: make this file non-executable in the actual contents"
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exit 1
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else
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echo "expected $expected and actual $actual match."
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echo 'OK'
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touch $out
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fi
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fi
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'';
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# See https://nixos.org/manual/nixpkgs/unstable/#tester-testVersion
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# or doc/builders/testers.chapter.md
testVersion =
{ package,
command ? "${package.meta.mainProgram or package.pname or package.name} --version",
+62
pkgs/build-support/testers/expect-failure.sh
···
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# Run a builder, flip exit code, save log and fix outputs
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#
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# Sub-goals:
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# - Delegate to another original builder passed via args
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# - Save the build log to output for further checks
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# - Make the derivation succeed if the original builder fails
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# - Make the derivation fail if the original builder returns exit code 0
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#
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# Requirements:
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# This runs before, without and after stdenv. Do not modify the environment;
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# especially not before invoking the original builder. For example, use
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# "@" substitutions instead of PATH.
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# Do not export any variables.
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# Stricter bash
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set -eu
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# ------------------------
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# Run the original builder
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echo "testBuildFailure: Expecting non-zero exit from builder and args: ${*@Q}"
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("$@" 2>&1) | @coreutils@/bin/tee $TMPDIR/testBuildFailure.log \
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| while read ln; do
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echo "original builder: $ln"
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done
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r=${PIPESTATUS[0]}
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if [[ $r = 0 ]]; then
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echo "testBuildFailure: The builder did not fail, but a failure was expected!"
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exit 1
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fi
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echo "testBuildFailure: Original builder produced exit code: $r"
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# -----------------------------------------
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# Write the build log to the default output
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outs=( $outputs )
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defOut=${outs[0]}
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defOutPath=${!defOut}
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if [[ ! -d $defOutPath ]]; then
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if [[ -e $defOutPath ]]; then
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@coreutils@/bin/mv $defOutPath $TMPDIR/out-node
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@coreutils@/bin/mkdir $defOutPath
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@coreutils@/bin/mv $TMPDIR/out-node $defOutPath/result
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fi
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fi
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@coreutils@/bin/mkdir -p $defOutPath
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@coreutils@/bin/mv $TMPDIR/testBuildFailure.log $defOutPath/testBuildFailure.log
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echo $r >$defOutPath/testBuildFailure.exit
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# ------------------------------------------------------
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# Put empty directories in place for any missing outputs
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for outputName in ${outputs:-out}; do
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outputPath="${!outputName}"
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if [[ ! -e "${outputPath}" ]]; then
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@coreutils@/bin/mkdir "${outputPath}";
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fi
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done
+164 -1
pkgs/build-support/testers/test/default.nix
···
-
{ testers, lib, pkgs, ... }:
+
{ testers, lib, pkgs, hello, runCommand, ... }:
let
pkgs-with-overlay = pkgs.extend(final: prev: {
proof-of-overlay-hello = prev.hello;
···
machine.succeed("hello | figlet >/dev/console")
'';
});
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testBuildFailure = lib.recurseIntoAttrs {
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happy = runCommand "testBuildFailure-happy" {
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failed = testers.testBuildFailure (runCommand "fail" {} ''
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echo ok-ish >$out
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echo failing though
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echo also stderr 1>&2
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exit 3
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'');
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} ''
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grep -F 'failing though' $failed/testBuildFailure.log
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grep -F 'also stderr' $failed/testBuildFailure.log
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grep -F 'ok-ish' $failed/result
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[[ 3 = $(cat $failed/testBuildFailure.exit) ]]
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touch $out
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'';
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helloDoesNotFail = runCommand "testBuildFailure-helloDoesNotFail" {
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failed = testers.testBuildFailure (testers.testBuildFailure hello);
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# Add hello itself as a prerequisite, so we don't try to run this test if
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# there's an actual failure in hello.
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inherit hello;
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} ''
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echo "Checking $failed/testBuildFailure.log"
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grep -F 'testBuildFailure: The builder did not fail, but a failure was expected' $failed/testBuildFailure.log
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[[ 1 = $(cat $failed/testBuildFailure.exit) ]]
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touch $out
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'';
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multiOutput = runCommand "testBuildFailure-multiOutput" {
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failed = testers.testBuildFailure (runCommand "fail" {
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# dev will be the default output
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outputs = ["dev" "doc" "out"];
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} ''
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echo i am failing
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exit 1
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'');
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} ''
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grep -F 'i am failing' $failed/testBuildFailure.log >/dev/null
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[[ 1 = $(cat $failed/testBuildFailure.exit) ]]
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# Checking our note that dev is the default output
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echo $failed/_ | grep -- '-dev/_' >/dev/null
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echo 'All good.'
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touch $out
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'';
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};
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testEqualContents = lib.recurseIntoAttrs {
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happy = testers.testEqualContents {
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assertion = "The same directory contents at different paths are recognized as equal";
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expected = runCommand "expected" {} ''
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mkdir -p $out/c
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echo a >$out/a
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echo b >$out/b
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echo d >$out/c/d
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'';
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actual = runCommand "actual" {} ''
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mkdir -p $out/c
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echo a >$out/a
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echo b >$out/b
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echo d >$out/c/d
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'';
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};
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unequalExe =
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runCommand "testEqualContents-unequalExe" {
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log = testers.testBuildFailure (testers.testEqualContents {
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assertion = "The same directory contents at different paths are recognized as equal";
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expected = runCommand "expected" {} ''
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mkdir -p $out/c
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echo a >$out/a
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chmod a+x $out/a
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echo b >$out/b
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echo d >$out/c/d
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'';
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actual = runCommand "actual" {} ''
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mkdir -p $out/c
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echo a >$out/a
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echo b >$out/b
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chmod a+x $out/b
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echo d >$out/c/d
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'';
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});
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} ''
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(
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set -x
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grep -F -- "executable bits don't match" $log/testBuildFailure.log
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grep -E -- '+.*-actual/a' $log/testBuildFailure.log
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grep -E -- '-.*-actual/b' $log/testBuildFailure.log
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grep -F -- "--- actual-executables" $log/testBuildFailure.log
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grep -F -- "+++ expected-executables" $log/testBuildFailure.log
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) || {
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echo "Test failed: could not find pattern in build log $log"
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exit 1
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}
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echo 'All good.'
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touch $out
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'';
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fileDiff =
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runCommand "testEqualContents-fileDiff" {
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log = testers.testBuildFailure (testers.testEqualContents {
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assertion = "The same directory contents at different paths are recognized as equal";
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expected = runCommand "expected" {} ''
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mkdir -p $out/c
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echo a >$out/a
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echo b >$out/b
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echo d >$out/c/d
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'';
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actual = runCommand "actual" {} ''
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mkdir -p $out/c
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echo a >$out/a
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echo B >$out/b
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echo d >$out/c/d
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'';
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});
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} ''
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(
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set -x
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grep -F -- "Contents must be equal but were not" $log/testBuildFailure.log
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grep -E -- '+++ .*-actual/b' $log/testBuildFailure.log
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grep -E -- '--- .*-actual/b' $log/testBuildFailure.log
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grep -F -- "-B" $log/testBuildFailure.log
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grep -F -- "+b" $log/testBuildFailure.log
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) || {
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echo "Test failed: could not find pattern in build log $log"
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exit 1
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}
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echo 'All good.'
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touch $out
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'';
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fileMissing =
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runCommand "testEqualContents-fileMissing" {
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log = testers.testBuildFailure (testers.testEqualContents {
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assertion = "The same directory contents at different paths are recognized as equal";
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expected = runCommand "expected" {} ''
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mkdir -p $out/c
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echo a >$out/a
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echo b >$out/b
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echo d >$out/c/d
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'';
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actual = runCommand "actual" {} ''
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mkdir -p $out/c
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echo a >$out/a
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echo d >$out/c/d
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'';
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});
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} ''
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(
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set -x
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grep -F -- "Contents must be equal but were not" $log/testBuildFailure.log
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grep -E -- 'Only in .*-expected: b' $log/testBuildFailure.log
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) || {
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echo "Test failed: could not find pattern in build log $log"
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exit 1
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}
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echo 'All good.'
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touch $out
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'';
+
};
}