Put functional tests in tests/functional

I think it is bad for these reasons when `tests/` contains a mix of
functional and integration tests

 - Concepts is harder to understand, the documentation makes a good
   unit vs functional vs integration distinction, but when the
   integration tests are just two subdirs within `tests/` this is not
   clear.

 - Source filtering in the `flake.nix` is more complex. We need to
   filter out some of the dirs from `tests/`, rather than simply pick
   the dirs we want and take all of them. This is a good sign the
   structure of what we are trying to do is not matching the structure
   of the files.

With this change we have a clean:
```shell-session
$ git show 'HEAD:tests'
tree HEAD:tests

functional/
installer/
nixos/
```

(cherry picked from commit 68c81c7375)

.github/labeler.yml

@@ -20,4 +20,4 @@
   # Unit tests
   - src/*/tests/**/*
   # Functional and integration tests
-  - tests/**/*
+  - tests/functional/**/*

.gitignore

@@ -79,24 +79,24 @@ perl/Makefile.config
 
 /src/build-remote/build-remote
 
-# /tests/
-/tests/test-tmp
-/tests/common/vars-and-functions.sh
-/tests/result*
-/tests/restricted-innocent
-/tests/shell
-/tests/shell.drv
-/tests/config.nix
-/tests/ca/config.nix
-/tests/dyn-drv/config.nix
-/tests/repl-result-out
-/tests/test-libstoreconsumer/test-libstoreconsumer
+# /tests/functional/
+/tests/functional/test-tmp
+/tests/functional/common/vars-and-functions.sh
+/tests/functional/result*
+/tests/functional/restricted-innocent
+/tests/functional/shell
+/tests/functional/shell.drv
+/tests/functional/config.nix
+/tests/functional/ca/config.nix
+/tests/functional/dyn-drv/config.nix
+/tests/functional/repl-result-out
+/tests/functional/test-libstoreconsumer/test-libstoreconsumer
 
-# /tests/lang/
-/tests/lang/*.out
-/tests/lang/*.out.xml
-/tests/lang/*.err
-/tests/lang/*.ast
+# /tests/functional/lang/
+/tests/functional/lang/*.out
+/tests/functional/lang/*.out.xml
+/tests/functional/lang/*.err
+/tests/functional/lang/*.ast
 
 /perl/lib/Nix/Config.pm
 /perl/lib/Nix/Store.cc

CONTRIBUTING.md

@@ -52,7 +52,7 @@ Check out the [security policy](https://github.com/NixOS/nix/security/policy).
 
    - [ ] Fixes an [idea approved](https://github.com/NixOS/nix/labels/idea%20approved) issue
    - [ ] Tests, as appropriate:
-     - Functional tests – [`tests/**.sh`](./tests)
+     - Functional tests – [`tests/functional/**.sh`](./tests/functional)
      - Unit tests – [`src/*/tests`](./src/)
      - Integration tests – [`tests/nixos/*`](./tests/nixos)
    - [ ] User documentation in the [manual](..doc/manual/src)

Makefile

@@ -26,11 +26,11 @@ makefiles += \
   src/libutil/tests/local.mk \
   src/libstore/tests/local.mk \
   src/libexpr/tests/local.mk \
-  tests/local.mk \
-  tests/ca/local.mk \
-  tests/dyn-drv/local.mk \
-  tests/test-libstoreconsumer/local.mk \
-  tests/plugins/local.mk
+  tests/functional/local.mk \
+  tests/functional/ca/local.mk \
+  tests/functional/dyn-drv/local.mk \
+  tests/functional/test-libstoreconsumer/local.mk \
+  tests/functional/plugins/local.mk
 else
 makefiles += \
   mk/disable-tests.mk

doc/manual/src/contributing/testing.md

@@ -12,7 +12,7 @@ Finer-grained filtering is also possible using the [--gtest_filter](https://goog
 
 ## Functional tests
 
-The functional tests reside under the `tests` directory and are listed in `tests/local.mk`.
+The functional tests reside under the `tests/functional` directory and are listed in `tests/functional/local.mk`.
 Each test is a bash script.
 
 ### Running the whole test suite
@@ -21,8 +21,8 @@ The whole test suite can be run with:
 
 ```shell-session
 $ make install && make installcheck
-ran test tests/foo.sh... [PASS]
-ran test tests/bar.sh... [PASS]
+ran test tests/functional/foo.sh... [PASS]
+ran test tests/functional/bar.sh... [PASS]
 ...
 ```
 
@@ -30,14 +30,14 @@ ran test tests/bar.sh... [PASS]
 
 Sometimes it is useful to group related tests so they can be easily run together without running the entire test suite.
 Each test group is in a subdirectory of `tests`.
-For example, `tests/ca/local.mk` defines a `ca` test group for content-addressed derivation outputs.
+For example, `tests/functional/ca/local.mk` defines a `ca` test group for content-addressed derivation outputs.
 
 That test group can be run like this:
 
 ```shell-session
 $ make ca.test-group -j50
-ran test tests/ca/nix-run.sh... [PASS]
-ran test tests/ca/import-derivation.sh... [PASS]
+ran test tests/functional/ca/nix-run.sh... [PASS]
+ran test tests/functional/ca/import-derivation.sh... [PASS]
 ...
 ```
 
@@ -56,21 +56,21 @@ install-tests-groups += $(test-group-name)
 Individual tests can be run with `make`:
 
 ```shell-session
-$ make tests/${testName}.sh.test
-ran test tests/${testName}.sh... [PASS]
+$ make tests/functional/${testName}.sh.test
+ran test tests/functional/${testName}.sh... [PASS]
 ```
 
 or without `make`:
 
 ```shell-session
-$ ./mk/run-test.sh tests/${testName}.sh
-ran test tests/${testName}.sh... [PASS]
+$ ./mk/run-test.sh tests/functional/${testName}.sh
+ran test tests/functional/${testName}.sh... [PASS]
 ```
 
 To see the complete output, one can also run:
 
 ```shell-session
-$ ./mk/debug-test.sh tests/${testName}.sh
+$ ./mk/debug-test.sh tests/functional/${testName}.sh
 + foo
 output from foo
 + bar
@@ -105,7 +105,7 @@ edit it like so:
 Then, running the test with `./mk/debug-test.sh` will drop you into GDB once the script reaches that point:
 
 ```shell-session
-$ ./mk/debug-test.sh tests/${testName}.sh
+$ ./mk/debug-test.sh tests/functional/${testName}.sh
 ...
 + gdb blash blub
 GNU gdb (GDB) 12.1
@@ -124,9 +124,11 @@ This technique is to include the exact output/behavior of a former version of Ni
 For example, this technique is used for the language tests, to check both the printed final value if evaluation was successful, and any errors and warnings encountered.
 
 It is frequently useful to regenerate the expected output.
-To do that, rerun the failed test with `_NIX_TEST_ACCEPT=1`.
-(At least, this is the convention we've used for `tests/lang.sh`.
-If we add more characterization testing we should always strive to be consistent.)
+To do that, rerun the failed test(s) with `_NIX_TEST_ACCEPT=1`.
+For example:
+```bash
+_NIX_TEST_ACCEPT=1 make tests/functional/lang.sh.test
+```
 
 An interesting situation to document is the case when these tests are "overfitted".
 The language tests are, again, an example of this.

flake.nix

@@ -24,7 +24,7 @@
       linuxSystems = linux32BitSystems ++ linux64BitSystems;
       darwinSystems = [ "x86_64-darwin" "aarch64-darwin" ];
       systems = linuxSystems ++ darwinSystems;
-      
+
       crossSystems = [ "armv6l-linux" "armv7l-linux" ];
 
       stdenvs = [ "gccStdenv" "clangStdenv" "clang11Stdenv" "stdenv" "libcxxStdenv" "ccacheStdenv" ];
@@ -58,35 +58,27 @@
 
       nixSrc = fileset.toSource {
         root = ./.;
-        fileset = fileset.intersect baseFiles (
-          fileset.difference
-            (fileset.unions [
-              ./.version
-              ./boehmgc-coroutine-sp-fallback.diff
-              ./bootstrap.sh
-              ./configure.ac
-              ./doc
-              ./local.mk
-              ./m4
-              ./Makefile
-              ./Makefile.config.in
-              ./misc
-              ./mk
-              ./precompiled-headers.h
-              ./src
-              ./tests
-              ./COPYING
-              ./scripts/local.mk
-              (fileset.fileFilter (f: lib.strings.hasPrefix "nix-profile" f.name) ./scripts)
-              # TODO: do we really need README.md? It doesn't seem used in the build.
-              ./README.md
-            ])
-            (fileset.unions [
-              # Removed file sets
-              ./tests/nixos
-              ./tests/installer
-            ])
-        );
+        fileset = fileset.intersect baseFiles (fileset.unions [
+          ./.version
+          ./boehmgc-coroutine-sp-fallback.diff
+          ./bootstrap.sh
+          ./configure.ac
+          ./doc
+          ./local.mk
+          ./m4
+          ./Makefile
+          ./Makefile.config.in
+          ./misc
+          ./mk
+          ./precompiled-headers.h
+          ./src
+          ./tests/functional
+          ./COPYING
+          ./scripts/local.mk
+          (fileset.fileFilter (f: lib.strings.hasPrefix "nix-profile" f.name) ./scripts)
+          # TODO: do we really need README.md? It doesn't seem used in the build.
+          ./README.md
+        ]);
       };
 
       # Memoize nixpkgs for different platforms for efficiency.

mk/common-test.sh

@@ -1,11 +1,15 @@
+test_dir=tests/functional
+
+test=$(echo -n "$test" | sed -e "s|^$test_dir/||")
+
 TESTS_ENVIRONMENT=("TEST_NAME=${test%.*}" 'NIX_REMOTE=')
 
 : ${BASH:=/usr/bin/env bash}
 
 init_test () {
-   cd tests && env "${TESTS_ENVIRONMENT[@]}" $BASH -e init.sh 2>/dev/null > /dev/null
+   cd "$test_dir" && env "${TESTS_ENVIRONMENT[@]}" $BASH -e init.sh 2>/dev/null > /dev/null
 }
 
 run_test_proper () {
-   cd $(dirname $test) && env "${TESTS_ENVIRONMENT[@]}" $BASH -e $(basename $test)
+   cd "$test_dir/$(dirname $test)" && env "${TESTS_ENVIRONMENT[@]}" $BASH -e $(basename $test)
 }

src/libstore/gc.cc

@@ -776,7 +776,7 @@ void LocalStore::collectGarbage(const GCOptions & options, GCResults & results)
         }
     };
 
-    /* Synchronisation point for testing, see tests/gc-concurrent.sh. */
+    /* Synchronisation point for testing, see tests/functional/gc-concurrent.sh. */
     if (auto p = getEnv("_NIX_TEST_GC_SYNC"))
         readFile(*p);
 

src/libutil/url-parts.hh

@@ -30,7 +30,7 @@ extern std::regex refRegex;
 
 /// Instead of defining what a good Git Ref is, we define what a bad Git Ref is
 /// This is because of the definition of a ref in refs.c in https://github.com/git/git
-/// See tests/fetchGitRefs.sh for the full definition
+/// See tests/functional/fetchGitRefs.sh for the full definition
 const static std::string badGitRefRegexS = "//|^[./]|/\\.|\\.\\.|[[:cntrl:][:space:]:?^~\[]|\\\\|\\*|\\.lock$|\\.lock/|@\\{|[/.]$|^@$|^$";
 extern std::regex badGitRefRegex;
 

tests/functional/bash-profile.sh

@@ -1,6 +1,6 @@
 source common.sh
 
-sed -e "s|@localstatedir@|$TEST_ROOT/profile-var|g" -e "s|@coreutils@|$coreutils|g" < ../scripts/nix-profile.sh.in > $TEST_ROOT/nix-profile.sh
+sed -e "s|@localstatedir@|$TEST_ROOT/profile-var|g" -e "s|@coreutils@|$coreutils|g" < ../../scripts/nix-profile.sh.in > $TEST_ROOT/nix-profile.sh
 
 user=$(whoami)
 rm -rf $TEST_HOME $TEST_ROOT/profile-var

tests/functional/build-remote-trustless.sh

@@ -6,7 +6,7 @@ unset NIX_STATE_DIR
 
 remoteDir=$TEST_ROOT/remote
 
-# Note: ssh{-ng}://localhost bypasses ssh. See tests/build-remote.sh for
+# Note: ssh{-ng}://localhost bypasses ssh. See tests/functional/build-remote.sh for
 # more details.
 nix-build $file -o $TEST_ROOT/result --max-jobs 0 \
   --arg busybox $busybox \

tests/functional/ca/local.mk

@@ -25,4 +25,4 @@ clean-files += \
   $(d)/config.nix
 
 test-deps += \
-  tests/ca/config.nix
+  tests/functional/ca/config.nix

tests/functional/common/vars-and-functions.sh.in

@@ -6,7 +6,7 @@ COMMON_VARS_AND_FUNCTIONS_SH_SOURCED=1
 
 export PS4='+(${BASH_SOURCE[0]-$0}:$LINENO) '
 
-export TEST_ROOT=$(realpath ${TMPDIR:-/tmp}/nix-test)/${TEST_NAME:-default}
+export TEST_ROOT=$(realpath ${TMPDIR:-/tmp}/nix-test)/${TEST_NAME:-default/tests\/functional//}
 export NIX_STORE_DIR
 if ! NIX_STORE_DIR=$(readlink -f $TEST_ROOT/store 2> /dev/null); then
     # Maybe the build directory is symlinked.

tests/functional/dyn-drv/local.mk

@@ -12,4 +12,4 @@ clean-files += \
   $(d)/config.nix
 
 test-deps += \
-  tests/dyn-drv/config.nix
+  tests/functional/dyn-drv/config.nix