Factor out a bit more language testings infra

Will be used in a second test after `lang.sh`.

maintainers/flake-module.nix

@@ -522,6 +522,7 @@
             ''^tests/functional/ca/repl\.sh$''
             ''^tests/functional/ca/selfref-gc\.sh$''
             ''^tests/functional/ca/why-depends\.sh$''
+            ''^tests/functional/characterisation-test-infra\.sh$''
             ''^tests/functional/check\.sh$''
             ''^tests/functional/common/vars-and-functions\.sh$''
             ''^tests/functional/completions\.sh$''
@@ -579,9 +580,7 @@
             ''^tests/functional/impure-env\.sh$''
             ''^tests/functional/impure-eval\.sh$''
             ''^tests/functional/install-darwin\.sh$''
-            ''^tests/functional/lang-test-infra\.sh$''
             ''^tests/functional/lang\.sh$''
-            ''^tests/functional/lang/framework\.sh$''
             ''^tests/functional/legacy-ssh-store\.sh$''
             ''^tests/functional/linux-sandbox\.sh$''
             ''^tests/functional/local-overlay-store/add-lower-inner\.sh$''

tests/functional/characterisation-test-infra.sh

@@ -3,7 +3,7 @@
 # Test the function for lang.sh
 source common.sh
 
-source lang/framework.sh
+source characterisation/framework.sh
 
 # We are testing this, so don't want outside world to affect us.
 unset _NIX_TEST_ACCEPT

tests/functional/characterisation/framework.sh

@@ -0,0 +1,77 @@
+# shellcheck shell=bash
+
+# Golden test support
+#
+# Test that the output of the given test matches what is expected. If
+# `_NIX_TEST_ACCEPT` is non-empty also update the expected output so
+# that next time the test succeeds.
+function diffAndAcceptInner() {
+    local -r testName=$1
+    local -r got="$2"
+    local -r expected="$3"
+
+    # Absence of expected file indicates empty output expected.
+    if test -e "$expected"; then
+        local -r expectedOrEmpty="$expected"
+    else
+        local -r expectedOrEmpty=characterisation/empty
+    fi
+
+    # Diff so we get a nice message
+    if ! diff --color=always --unified "$expectedOrEmpty" "$got"; then
+        echo "FAIL: evaluation result of $testName not as expected"
+        # shellcheck disable=SC2034
+        badDiff=1
+    fi
+
+    # Update expected if `_NIX_TEST_ACCEPT` is non-empty.
+    if test -n "${_NIX_TEST_ACCEPT-}"; then
+        cp "$got" "$expected"
+        # Delete empty expected files to avoid bloating the repo with
+        # empty files.
+        if ! test -s "$expected"; then
+            rm "$expected"
+        fi
+    fi
+}
+
+function characterisationTestExit() {
+    # Make sure shellcheck knows all these will be defined by the caller
+    : "${badDiff?} ${badExitCode?}"
+
+    if test -n "${_NIX_TEST_ACCEPT-}"; then
+        if (( "$badDiff" )); then
+            set +x
+            echo 'Output did mot match, but accepted output as the persisted expected output.'
+            echo 'That means the next time the tests are run, they should pass.'
+            set -x
+        else
+            set +x
+            echo 'NOTE: Environment variable _NIX_TEST_ACCEPT is defined,'
+            echo 'indicating the unexpected output should be accepted as the expected output going forward,'
+            echo 'but no tests had unexpected output so there was no expected output to update.'
+            set -x
+        fi
+        if (( "$badExitCode" )); then
+            exit "$badExitCode"
+        else
+            skipTest "regenerating golden masters"
+        fi
+    else
+        if (( "$badDiff" )); then
+            set +x
+            echo ''
+            echo 'You can rerun this test with:'
+            echo ''
+            echo "    _NIX_TEST_ACCEPT=1 make tests/functional/${TEST_NAME}.test"
+            echo ''
+            echo 'to regenerate the files containing the expected output,'
+            echo 'and then view the git diff to decide whether a change is'
+            echo 'good/intentional or bad/unintentional.'
+            echo 'If the diff contains arbitrary or impure information,'
+            echo 'please improve the normalization that the test applies to the output.'
+            set -x
+        fi
+        exit $(( "$badExitCode" + "$badDiff" ))
+    fi
+}

tests/functional/lang.sh

@@ -4,7 +4,7 @@ source common.sh
 
 set -o pipefail
 
-source lang/framework.sh
+source characterisation/framework.sh
 
 # specialize function a bit
 function diffAndAccept() {
@@ -138,32 +138,4 @@ for i in lang/eval-okay-*.nix; do
     fi
 done
 
-if test -n "${_NIX_TEST_ACCEPT-}"; then
-    if (( "$badDiff" )); then
-        echo 'Output did mot match, but accepted output as the persisted expected output.'
-        echo 'That means the next time the tests are run, they should pass.'
-    else
-        echo 'NOTE: Environment variable _NIX_TEST_ACCEPT is defined,'
-        echo 'indicating the unexpected output should be accepted as the expected output going forward,'
-        echo 'but no tests had unexpected output so there was no expected output to update.'
-    fi
-    if (( "$badExitCode" )); then
-        exit "$badExitCode"
-    else
-        skipTest "regenerating golden masters"
-    fi
-else
-    if (( "$badDiff" )); then
-        echo ''
-        echo 'You can rerun this test with:'
-        echo ''
-        echo '    _NIX_TEST_ACCEPT=1 make tests/functional/lang.sh.test'
-        echo ''
-        echo 'to regenerate the files containing the expected output,'
-        echo 'and then view the git diff to decide whether a change is'
-        echo 'good/intentional or bad/unintentional.'
-        echo 'If the diff contains arbitrary or impure information,'
-        echo 'please improve the normalization that the test applies to the output.'
-    fi
-    exit $(( "$badExitCode" + "$badDiff" ))
-fi
+characterisationTestExit

tests/functional/lang/framework.sh

@@ -1,33 +0,0 @@
-# Golden test support
-#
-# Test that the output of the given test matches what is expected. If
-# `_NIX_TEST_ACCEPT` is non-empty also update the expected output so
-# that next time the test succeeds.
-function diffAndAcceptInner() {
-    local -r testName=$1
-    local -r got="$2"
-    local -r expected="$3"
-
-    # Absence of expected file indicates empty output expected.
-    if test -e "$expected"; then
-        local -r expectedOrEmpty="$expected"
-    else
-        local -r expectedOrEmpty=lang/empty.exp
-    fi
-
-    # Diff so we get a nice message
-    if ! diff --color=always --unified "$expectedOrEmpty" "$got"; then
-        echo "FAIL: evaluation result of $testName not as expected"
-        badDiff=1
-    fi
-
-    # Update expected if `_NIX_TEST_ACCEPT` is non-empty.
-    if test -n "${_NIX_TEST_ACCEPT-}"; then
-        cp "$got" "$expected"
-        # Delete empty expected files to avoid bloating the repo with
-        # empty files.
-        if ! test -s "$expected"; then
-            rm "$expected"
-        fi
-    fi
-}

tests/functional/local.mk

@@ -23,7 +23,7 @@ nix_tests = \
   remote-store.sh \
   legacy-ssh-store.sh \
   lang.sh \
-  lang-test-infra.sh \
+  characterisation-test-infra.sh \
   experimental-features.sh \
   fetchMercurial.sh \
   gc-auto.sh \