build-support/fetchgitlab: remove throwIfNot usage

pkgs/build-support/fetchgitlab/default.nix

@@ -64,43 +64,46 @@ lib.makeOverridable (
     fetcher = if useFetchGit then fetchgit else fetchzip;
 
     privateAttrs = lib.optionalAttrs private (
-      lib.throwIfNot (protocol == "https") "private token login is only supported for https" {
-        netrcPhase = ''
-          if [ -z "''$${varBase}USERNAME" -o -z "''$${varBase}PASSWORD" ]; then
-            echo "Error: Private fetchFromGitLab requires the nix building process (nix-daemon in multi user mode) to have the ${varBase}USERNAME and ${varBase}PASSWORD env vars set." >&2
-            exit 1
-          fi
-        ''
-        + (
-          if useFetchGit then
-            # GitLab supports HTTP Basic Authentication only when Git is used:
-            # https://docs.gitlab.com/ee/user/project/settings/project_access_tokens.html#project-access-tokens
-            ''
-              cat > netrc <<EOF
-              machine ${domain}
-                      login ''$${varBase}USERNAME
-                      password ''$${varBase}PASSWORD
-              EOF
-            ''
-          else
-            # Access via the GitLab API requires a custom header and does not work
-            # with HTTP Basic Authentication:
-            # https://docs.gitlab.com/ee/api/#personalprojectgroup-access-tokens
-            ''
-              # needed because fetchurl always sets --netrc-file if a netrcPhase is present
-              touch netrc
+      if protocol != "https" then
+        throw "private token login is only supported for https"
+      else
+        {
+          netrcPhase = ''
+            if [ -z "''$${varBase}USERNAME" -o -z "''$${varBase}PASSWORD" ]; then
+              echo "Error: Private fetchFromGitLab requires the nix building process (nix-daemon in multi user mode) to have the ${varBase}USERNAME and ${varBase}PASSWORD env vars set." >&2
+              exit 1
+            fi
+          ''
+          + (
+            if useFetchGit then
+              # GitLab supports HTTP Basic Authentication only when Git is used:
+              # https://docs.gitlab.com/ee/user/project/settings/project_access_tokens.html#project-access-tokens
+              ''
+                cat > netrc <<EOF
+                machine ${domain}
+                        login ''$${varBase}USERNAME
+                        password ''$${varBase}PASSWORD
+                EOF
+              ''
+            else
+              # Access via the GitLab API requires a custom header and does not work
+              # with HTTP Basic Authentication:
+              # https://docs.gitlab.com/ee/api/#personalprojectgroup-access-tokens
+              ''
+                # needed because fetchurl always sets --netrc-file if a netrcPhase is present
+                touch netrc
 
-              cat > private-token <<EOF
-              PRIVATE-TOKEN: ''$${varBase}PASSWORD
-              EOF
-              curlOpts="$curlOpts --header @./private-token"
-            ''
-        );
-        netrcImpureEnvVars = [
-          "${varBase}USERNAME"
-          "${varBase}PASSWORD"
-        ];
-      }
+                cat > private-token <<EOF
+                PRIVATE-TOKEN: ''$${varBase}PASSWORD
+                EOF
+                curlOpts="$curlOpts --header @./private-token"
+              ''
+          );
+          netrcImpureEnvVars = [
+            "${varBase}USERNAME"
+            "${varBase}PASSWORD"
+          ];
+        }
     );
 
     gitRepoUrl = "${protocol}://${domain}/${slug}.git";