Merge branch 'jk/test-lazy-prereq-heredoc' into jch

The lazy prerequisite set-up script can be fed as a here-doc, just
like test_expect_{success,failure} scripts these days.

* jk/test-lazy-prereq-heredoc:
  test-lib: allow lazy prerequisite snippets as here-docs

t/t5551-http-fetch-smart.sh

@@ -21,14 +21,14 @@ start_httpd
 # authentication after an early HTTP/2 response. This bug was introduced
 # in cURL v7.88.0 (8c762f5998 (http2: minor buffer and error path fixes,
 # 2023-02-08)) and fixed in v8.3.0 (https://github.com/curl/curl/pull/11756).
-test_lazy_prereq HAVE_CURL_HTTP2_BUG '
+test_lazy_prereq HAVE_CURL_HTTP2_BUG - <<\EOT
 	test_have_prereq HTTP2 &&
 	build_option libcurl |
-	awk -F. '\''
+	awk -F. '
 		($1 == 7 && $2 >= 88) || ($1 == 8 && $2 < 3) { broken = 1 }
 		END { exit !broken }
-	'\''
-'
+	'
+EOT
 
 test_expect_success HTTP2 'enable client-side http/2' '
 	git config --global http.version HTTP/2

t/test-lib-functions.sh

@@ -760,7 +760,7 @@ lazily_testable_prereq= lazily_tested_prereq=
 # Usage: test_lazy_prereq PREREQ 'script'
 test_lazy_prereq () {
 	lazily_testable_prereq="$lazily_testable_prereq$1 "
-	eval test_prereq_lazily_$1=\$2
+	test_body_or_stdin "test_prereq_lazily_$1" "$2"
 }
 
 test_run_lazy_prereq_ () {