tests: auto-set LIB_HTTPD_PORT from test name

We set the default apache port for each of the httpd tests
to the 4-digit test number of the test script. We want these
to remain unique so that the tests do not conflict with each
other when run in parallel.

Instead of doing it manually in each test script, let's just
set it from the test name at run time. This is simpler, and
is one less thing to be updated when test scripts are
renamed (e.g., when being re-rolled or when conflicting
after being merged with another topic).

Incidentally, this fixes a case where t5537 and t5538 used
the same port number (5537), and could conflict with each
other when run in parallel.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/t/lib-httpd.sh b/t/lib-httpd.sh
index bfdff2a..b43162e 100644
--- a/t/lib-httpd.sh
+++ b/t/lib-httpd.sh
@@ -64,7 +64,7 @@
 esac
 
 LIB_HTTPD_PATH=${LIB_HTTPD_PATH-"$DEFAULT_HTTPD_PATH"}
-LIB_HTTPD_PORT=${LIB_HTTPD_PORT-'8111'}
+LIB_HTTPD_PORT=${LIB_HTTPD_PORT-${this_test#t}}
 
 TEST_PATH="$TEST_DIRECTORY"/lib-httpd
 HTTPD_ROOT_PATH="$PWD"/httpd
diff --git a/t/t5537-fetch-shallow.sh b/t/t5537-fetch-shallow.sh
index b0fa738..adf215a 100755
--- a/t/t5537-fetch-shallow.sh
+++ b/t/t5537-fetch-shallow.sh
@@ -178,7 +178,6 @@
 	test_done
 fi
 
-LIB_HTTPD_PORT=${LIB_HTTPD_PORT-'5537'}
 . "$TEST_DIRECTORY"/lib-httpd.sh
 start_httpd
 
diff --git a/t/t5538-push-shallow.sh b/t/t5538-push-shallow.sh
index 0a6e40f..8e54ac5 100755
--- a/t/t5538-push-shallow.sh
+++ b/t/t5538-push-shallow.sh
@@ -126,7 +126,6 @@
 	test_done
 fi
 
-LIB_HTTPD_PORT=${LIB_HTTPD_PORT-'5537'}
 . "$TEST_DIRECTORY"/lib-httpd.sh
 start_httpd
 
diff --git a/t/t5540-http-push.sh b/t/t5540-http-push.sh
index 5b0198c..8d7b3c5 100755
--- a/t/t5540-http-push.sh
+++ b/t/t5540-http-push.sh
@@ -16,7 +16,6 @@
 fi
 
 LIB_HTTPD_DAV=t
-LIB_HTTPD_PORT=${LIB_HTTPD_PORT-'5540'}
 . "$TEST_DIRECTORY"/lib-httpd.sh
 ROOT_PATH="$PWD"
 start_httpd
diff --git a/t/t5541-http-push.sh b/t/t5541-http-push.sh
index bfd241e..73af16f 100755
--- a/t/t5541-http-push.sh
+++ b/t/t5541-http-push.sh
@@ -12,7 +12,6 @@
 fi
 
 ROOT_PATH="$PWD"
-LIB_HTTPD_PORT=${LIB_HTTPD_PORT-'5541'}
 . "$TEST_DIRECTORY"/lib-httpd.sh
 . "$TEST_DIRECTORY"/lib-terminal.sh
 start_httpd
diff --git a/t/t5550-http-fetch.sh b/t/t5550-http-fetch.sh
index 8392624..1a3a2b6 100755
--- a/t/t5550-http-fetch.sh
+++ b/t/t5550-http-fetch.sh
@@ -8,7 +8,6 @@
 	test_done
 fi
 
-LIB_HTTPD_PORT=${LIB_HTTPD_PORT-'5550'}
 . "$TEST_DIRECTORY"/lib-httpd.sh
 start_httpd
 
diff --git a/t/t5551-http-fetch.sh b/t/t5551-http-fetch.sh
index a124efe..e07eaf3 100755
--- a/t/t5551-http-fetch.sh
+++ b/t/t5551-http-fetch.sh
@@ -8,7 +8,6 @@
 	test_done
 fi
 
-LIB_HTTPD_PORT=${LIB_HTTPD_PORT-'5551'}
 . "$TEST_DIRECTORY"/lib-httpd.sh
 start_httpd
 
diff --git a/t/t5561-http-backend.sh b/t/t5561-http-backend.sh
index b5d7fbc..d23fb02 100755
--- a/t/t5561-http-backend.sh
+++ b/t/t5561-http-backend.sh
@@ -8,7 +8,6 @@
 	test_done
 fi
 
-LIB_HTTPD_PORT=${LIB_HTTPD_PORT-'5561'}
 . "$TEST_DIRECTORY"/lib-httpd.sh
 start_httpd