1 files changed, 49 insertions, 0 deletions
diff --git a/nixpkgs/pkgs/build-support/testers/hasPkgConfigModules/tests.nix b/nixpkgs/pkgs/build-support/testers/hasPkgConfigModules/tests.nix
new file mode 100644
index 000000000000..96569498fb15
--- /dev/null
+++ b/nixpkgs/pkgs/build-support/testers/hasPkgConfigModules/tests.nix
@@ -0,0 +1,49 @@
+# cd nixpkgs
+# nix-build -A tests.testers.hasPkgConfigModule
+{ lib, testers, zlib, openssl, runCommand }:
+
+lib.recurseIntoAttrs {
+
+  zlib-has-zlib = testers.hasPkgConfigModules {
+    package = zlib;
+    moduleNames = [ "zlib" ];
+  };
+
+  zlib-has-meta-pkgConfigModules = testers.hasPkgConfigModules {
+    package = zlib;
+  };
+
+  openssl-has-openssl = testers.hasPkgConfigModules {
+    package = openssl;
+    moduleNames = [ "openssl" ];
+  };
+
+  openssl-has-all-meta-pkgConfigModules = testers.hasPkgConfigModules {
+    package = openssl;
+  };
+
+  zlib-does-not-have-ylib = runCommand "zlib-does-not-have-ylib" {
+    failed = testers.testBuildFailure (
+      testers.hasPkgConfigModules {
+      package = zlib;
+      moduleNames = [ "ylib" ];
+      }
+    );
+  } ''
+    echo 'it logs a relevant error message'
+    {
+      grep -F "pkg-config module ylib was not found" $failed/testBuildFailure.log
+    }
+
+    echo 'it logs which pkg-config modules are available, to be helpful'
+    {
+      # grep -v: the string zlib does also occur in a store path in an earlier message, which isn't particularly helpful
+      grep -v "checking pkg-config module" < $failed/testBuildFailure.log \
+        | grep -F "zlib"
+    }
+
+    # done
+    touch $out
+  '';
+
+}