Throw nice error if server is too old to support psql's \ef or \sf command.

Previously, you'd get "function pg_catalog.pg_get_functiondef(integer) does
not exist", which is at best rather unprofessional-looking.  Back-patch
to 8.4 where \ef was introduced.

Josh Kupershmidt

diff --git a/src/bin/psql/command.c b/src/bin/psql/command.c
index 2c389021be7b99e70815e65ad365d88eb5d9e397..5970ab32c15b34cbc35e4929c0fc0669f1fa028d 100644 (file)
--- a/src/bin/psql/command.c
+++ b/src/bin/psql/command.c
@@ -583,7 +583,13 @@ exec_command(const char *cmd,
    {
        int         lineno = -1;
 
-       if (!query_buf)
+       if (pset.sversion < 80400)
+       {
+           psql_error("The server (version %d.%d) does not support editing function source.\n",
+                      pset.sversion / 10000, (pset.sversion / 100) % 100);
+           status = PSQL_CMD_ERROR;
+       }
+       else if (!query_buf)
        {
            psql_error("no query buffer\n");
            status = PSQL_CMD_ERROR;
@@ -1115,7 +1121,13 @@ exec_command(const char *cmd,
        func_buf = createPQExpBuffer();
        func = psql_scan_slash_option(scan_state,
                                      OT_WHOLE_LINE, NULL, true);
-       if (!func)
+       if (pset.sversion < 80400)
+       {
+           psql_error("The server (version %d.%d) does not support showing function source.\n",
+                      pset.sversion / 10000, (pset.sversion / 100) % 100);
+           status = PSQL_CMD_ERROR;
+       }
+       else if (!func)
        {
            psql_error("function name is required\n");
            status = PSQL_CMD_ERROR;