diff --git a/doc/src/sgml/ref/psql-ref.sgml b/doc/src/sgml/ref/psql-ref.sgml
index ae58708..dac8e37 100644
--- a/doc/src/sgml/ref/psql-ref.sgml
+++ b/doc/src/sgml/ref/psql-ref.sgml
@@ -2035,6 +2035,79 @@ hello 10
+
+ \if expr
+ \elif expr
+ \else
+ \endif
+
+
+ This group of commands implements nestable conditional blocks, like
+ this:
+
+
+-- set ON_ERROR_STOP in case the variables are not valid boolean expressions
+\set ON_ERROR_STOP on
+SELECT
+ EXISTS(SELECT 1 FROM customer WHERE customer_id = 123) as is_customer,
+ EXISTS(SELECT 1 FROM employee WHERE employee_id = 456) as is_employee
+\gset
+\if :is_customer
+ SELECT * FROM customer WHERE customer_id = 123;
+\elif :is_employee
+ \echo 'is not a customer but is an employee'
+ SELECT * FROM employee WHERE employee_id = 456;
+\else
+ \if yes
+ \echo 'not a customer or employee'
+ \else
+ \echo 'this should never print'
+ \endif
+\endif
+
+
+ Conditional blocks must begin with a \if and end
+ with an \endif, and the pairs must be found in
+ the same source file. If an EOF is reached on the main file or an
+ \include-ed file before all local
+ \if-\endif are matched, then
+ psql will raise an error.
+
+
+ A conditional block can have any number of
+ \elif clauses, which may optionally be followed by a
+ single \else clause.
+
+
+ The \if and \elif commands
+ read the rest of the line and evaluate it as a boolean expression.
+ Currently, expressions are limited to a single unquoted string
+ which are evaluated like other on/off options, so the valid values
+ are any unambiguous case insensitive matches for one of:
+ true, false, 1,
+ 0, on, off,
+ yes, no. So
+ t, T, and tR
+ will all match true.
+
+ Expressions that do not properly evaluate to true or false will
+ generate an error and cause the \if or
+ \elif command to fail. Because that behavior may
+ change branching context in undesirable ways (executing code which
+ was intended to be skipped, causing \elif,
+ \else, and \endif commands to
+ pair with the wrong \if, etc), it is
+ recommended that scripts which use conditionals also set
+ ON_ERROR_STOP.
+
+
+ Lines within false branches are not evaluated in any way: queries are
+ not sent to the server, non-conditional commands are not evaluated but
+ bluntly ignored, nested if-expressions in such branches are also not
+ evaluated but are tallied to check for proper nesting.
+
+
+
\ir or \include_relative filename
diff --git a/src/bin/psql/Makefile b/src/bin/psql/Makefile
index c53733f..1492b66 100644
--- a/src/bin/psql/Makefile
+++ b/src/bin/psql/Makefile
@@ -21,7 +21,7 @@ REFDOCDIR= $(top_srcdir)/doc/src/sgml/ref
override CPPFLAGS := -I. -I$(srcdir) -I$(libpq_srcdir) $(CPPFLAGS)
LDFLAGS += -L$(top_builddir)/src/fe_utils -lpgfeutils -lpq
-OBJS= command.o common.o help.o input.o stringutils.o mainloop.o copy.o \
+OBJS= command.o common.o conditional.o help.o input.o stringutils.o mainloop.o copy.o \
startup.o prompt.o variables.o large_obj.o describe.o \
crosstabview.o tab-complete.o \
sql_help.o psqlscanslash.o \
@@ -61,8 +61,16 @@ uninstall:
clean distclean:
rm -f psql$(X) $(OBJS) lex.backup
+ rm -rf tmp_check
# files removed here are supposed to be in the distribution tarball,
# so do not clean them in the clean/distclean rules
maintainer-clean: distclean
rm -f sql_help.h sql_help.c psqlscanslash.c
+
+
+check:
+ $(prove_check)
+
+installcheck:
+ $(prove_installcheck)
diff --git a/src/bin/psql/command.c b/src/bin/psql/command.c
index f17f610..6c15c01 100644
--- a/src/bin/psql/command.c
+++ b/src/bin/psql/command.c
@@ -38,6 +38,7 @@
#include "fe_utils/string_utils.h"
#include "common.h"
+#include "conditional.h"
#include "copy.h"
#include "crosstabview.h"
#include "describe.h"
@@ -62,6 +63,7 @@ typedef enum EditableObjectType
/* functions for use in this file */
static backslashResult exec_command(const char *cmd,
PsqlScanState scan_state,
+ ConditionalStack cstack,
PQExpBuffer query_buf);
static bool do_edit(const char *filename_arg, PQExpBuffer query_buf,
int lineno, bool *edited);
@@ -109,6 +111,7 @@ static void checkWin32Codepage(void);
backslashResult
HandleSlashCmds(PsqlScanState scan_state,
+ ConditionalStack cstack,
PQExpBuffer query_buf)
{
backslashResult status = PSQL_CMD_SKIP_LINE;
@@ -121,7 +124,7 @@ HandleSlashCmds(PsqlScanState scan_state,
cmd = psql_scan_slash_command(scan_state);
/* And try to execute it */
- status = exec_command(cmd, scan_state, query_buf);
+ status = exec_command(cmd, scan_state, cstack, query_buf);
if (status == PSQL_CMD_UNKNOWN)
{
@@ -132,7 +135,7 @@ HandleSlashCmds(PsqlScanState scan_state,
status = PSQL_CMD_ERROR;
}
- if (status != PSQL_CMD_ERROR)
+ if (status != PSQL_CMD_ERROR && conditional_active(cstack))
{
/* eat any remaining arguments after a valid command */
/* note we suppress evaluation of backticks here */
@@ -194,6 +197,30 @@ read_connect_arg(PsqlScanState scan_state)
return result;
}
+/*
+ * Read and interpret argument as a boolean expression.
+ * Return true if a boolean value was successfully parsed.
+ */
+static bool
+read_boolean_expression(PsqlScanState scan_state, char *action,
+ bool *result)
+{
+ char *value = psql_scan_slash_option(scan_state,
+ OT_NORMAL, NULL, false);
+ bool success = ParseVariableBool(value, action, result);
+ free(value);
+ return success;
+}
+
+/*
+ * Return true if the command given is a branching command.
+ */
+static bool
+is_branching_command(const char *cmd)
+{
+ return (strcmp(cmd, "if") == 0 || strcmp(cmd, "elif") == 0
+ || strcmp(cmd, "else") == 0 || strcmp(cmd, "endif") == 0);
+}
/*
* Subroutine to actually try to execute a backslash command.
@@ -201,12 +228,25 @@ read_connect_arg(PsqlScanState scan_state)
static backslashResult
exec_command(const char *cmd,
PsqlScanState scan_state,
+ ConditionalStack cstack,
PQExpBuffer query_buf)
{
bool success = true; /* indicate here if the command ran ok or
* failed */
backslashResult status = PSQL_CMD_SKIP_LINE;
+ if (!conditional_active(cstack) && !is_branching_command(cmd))
+ {
+ if (pset.cur_cmd_interactive)
+ psql_error("command ignored, use \\endif or Ctrl-C to exit "
+ "current branch.\n");
+
+ /* Continue with an empty buffer as if the command were never read */
+ resetPQExpBuffer(query_buf);
+ psql_scan_reset(scan_state);
+ return status;
+ }
+
/*
* \a -- toggle field alignment This makes little sense but we keep it
* around.
@@ -1006,6 +1046,141 @@ exec_command(const char *cmd,
}
}
+ /*
+ * \if is the beginning of an \if..\endif block. must be a
+ * valid boolean expression, or the command will be ignored. If this \if
+ * is itself a part of a branch that is false/ignored, it too will
+ * automatically be ignored.
+ */
+ else if (strcmp(cmd, "if") == 0)
+ {
+ /*
+ * only evaluate the expression for truth if the underlying
+ * branch is active
+ */
+ if (conditional_active(cstack))
+ {
+ bool if_true = false;
+ success = read_boolean_expression(scan_state, "\\if ", &if_true);
+ if (success)
+ conditional_stack_push(cstack,
+ (if_true) ? IFSTATE_TRUE : IFSTATE_FALSE);
+ }
+ psql_scan_reset(scan_state);
+ }
+
+ /*
+ * \elif is part of an \if..\endif block
+ * will only be evalated for boolean truth if no previous
+ * \if or \endif in the block has evaluated to true and the \if..\endif
+ * block is not itself being ignored.
+ * in the event that does not conform to a proper boolean expression,
+ * all following statements in the block will be ignored until \endif is
+ * encountered.
+ *
+ */
+ else if (strcmp(cmd, "elif") == 0)
+ {
+ bool elif_true = false;
+ switch (conditional_stack_peek(cstack))
+ {
+ case IFSTATE_IGNORED:
+ /*
+ * inactive branch, do nothing:
+ * either if-endif already had a true block,
+ * or whole parent block is false.
+ */
+ break;
+ case IFSTATE_TRUE:
+ /*
+ * just finished true section of active branch
+ * do not evaluate expression, just skip
+ */
+ conditional_stack_poke(cstack, IFSTATE_IGNORED);
+ break;
+ case IFSTATE_FALSE:
+ /*
+ * have not yet found a true block in this if-endif,
+ * determine if this section is true or not.
+ * variable expansion must be temporarily turned back
+ * on to read the boolean expression.
+ */
+ success = read_boolean_expression(scan_state, "\\elif ",
+ &elif_true);
+ if (success && elif_true)
+ conditional_stack_poke(cstack, IFSTATE_TRUE);
+ break;
+ case IFSTATE_ELSE_TRUE:
+ case IFSTATE_ELSE_FALSE:
+ psql_error("\\elif: cannot occur after \\else\n");
+ success = false;
+ break;
+ case IFSTATE_NONE:
+ /* no if to elif from */
+ psql_error("\\elif: no matching \\if\n");
+ success = false;
+ break;
+ default:
+ break;
+ }
+ psql_scan_reset(scan_state);
+ }
+
+ /*
+ * \else is part of an \if..\endif block
+ * the statements within an \else branch will only be executed if
+ * all previous \if and \endif expressions evaluated to false
+ * and the block was not itself being ignored.
+ */
+ else if (strcmp(cmd, "else") == 0)
+ {
+ switch (conditional_stack_peek(cstack))
+ {
+ case IFSTATE_FALSE:
+ /* just finished false section of an active branch */
+ conditional_stack_poke(cstack, IFSTATE_ELSE_TRUE);
+ break;
+ case IFSTATE_TRUE:
+ case IFSTATE_IGNORED:
+ /*
+ * either just finished true section of an active branch,
+ * or whole branch was inactive. either way, be on the
+ * lookout for any invalid \endif or \else commands
+ */
+ conditional_stack_poke(cstack, IFSTATE_ELSE_FALSE);
+ break;
+ case IFSTATE_NONE:
+ /* no if to else from */
+ psql_error("\\else: no matching \\if\n");
+ success = false;
+ break;
+ case IFSTATE_ELSE_TRUE:
+ case IFSTATE_ELSE_FALSE:
+ psql_error("\\else: cannot occur after \\else\n");
+ success = false;
+ break;
+ default:
+ break;
+ }
+ psql_scan_reset(scan_state);
+ }
+
+ /*
+ * \endif - closing statment of an \if...\endif block
+ */
+ else if (strcmp(cmd, "endif") == 0)
+ {
+ /*
+ * get rid of this ifstate element and look at the previous
+ * one, if any
+ */
+ success = conditional_stack_pop(cstack);
+ if (!success)
+ psql_error("\\endif: no matching \\if\n");
+
+ psql_scan_reset(scan_state);
+ }
+
/* \l is list databases */
else if (strcmp(cmd, "l") == 0 || strcmp(cmd, "list") == 0 ||
strcmp(cmd, "l+") == 0 || strcmp(cmd, "list+") == 0)
diff --git a/src/bin/psql/command.h b/src/bin/psql/command.h
index d0c3264..a396f29 100644
--- a/src/bin/psql/command.h
+++ b/src/bin/psql/command.h
@@ -10,6 +10,7 @@
#include "fe_utils/print.h"
#include "fe_utils/psqlscan.h"
+#include "conditional.h"
typedef enum _backslashResult
@@ -25,6 +26,7 @@ typedef enum _backslashResult
extern backslashResult HandleSlashCmds(PsqlScanState scan_state,
+ ConditionalStack cstack,
PQExpBuffer query_buf);
extern int process_file(char *filename, bool use_relative_path);
diff --git a/src/bin/psql/common.c b/src/bin/psql/common.c
index 5349c39..665bfef 100644
--- a/src/bin/psql/common.c
+++ b/src/bin/psql/common.c
@@ -119,6 +119,11 @@ setQFout(const char *fname)
* If "escape" is true, return the value suitably quoted and escaped,
* as an identifier or string literal depending on "as_ident".
* (Failure in escaping should lead to returning NULL.)
+ *
+ * Variables are not expanded if the current branch is inactive
+ * (part of an \if..\endif section which is false). \elif branches
+ * will need temporarily mark the branch active in order to
+ * properly evaluate conditionals.
*/
char *
psql_get_variable(const char *varname, bool escape, bool as_ident)
diff --git a/src/bin/psql/copy.c b/src/bin/psql/copy.c
index 481031a..6cfd438 100644
--- a/src/bin/psql/copy.c
+++ b/src/bin/psql/copy.c
@@ -23,6 +23,7 @@
#include "common.h"
#include "prompt.h"
#include "stringutils.h"
+#include "conditional.h"
/*
@@ -552,7 +553,7 @@ handleCopyIn(PGconn *conn, FILE *copystream, bool isbinary, PGresult **res)
/* interactive input probably silly, but give one prompt anyway */
if (showprompt)
{
- const char *prompt = get_prompt(PROMPT_COPY);
+ const char *prompt = get_prompt(PROMPT_COPY, (ConditionalStack) NULL);
fputs(prompt, stdout);
fflush(stdout);
@@ -590,7 +591,8 @@ handleCopyIn(PGconn *conn, FILE *copystream, bool isbinary, PGresult **res)
if (showprompt)
{
- const char *prompt = get_prompt(PROMPT_COPY);
+ const char *prompt = get_prompt(PROMPT_COPY,
+ (ConditionalStack) NULL);
fputs(prompt, stdout);
fflush(stdout);
diff --git a/src/bin/psql/help.c b/src/bin/psql/help.c
index 3e3cab4..9f9e1a6 100644
--- a/src/bin/psql/help.c
+++ b/src/bin/psql/help.c
@@ -210,6 +210,13 @@ slashUsage(unsigned short int pager)
fprintf(output, _(" \\qecho [STRING] write string to query output stream (see \\o)\n"));
fprintf(output, "\n");
+ fprintf(output, _("Conditionals\n"));
+ fprintf(output, _(" \\if begin a conditional block\n"));
+ fprintf(output, _(" \\elif else if in the current conditional block\n"));
+ fprintf(output, _(" \\else else in the current conditional block\n"));
+ fprintf(output, _(" \\endif end current conditional block\n"));
+ fprintf(output, "\n");
+
fprintf(output, _("Informational\n"));
fprintf(output, _(" (options: S = show system objects, + = additional detail)\n"));
fprintf(output, _(" \\d[S+] list tables, views, and sequences\n"));
diff --git a/src/bin/psql/mainloop.c b/src/bin/psql/mainloop.c
index 6e358e2..9d3069e 100644
--- a/src/bin/psql/mainloop.c
+++ b/src/bin/psql/mainloop.c
@@ -10,12 +10,13 @@
#include "command.h"
#include "common.h"
+#include "conditional.h"
#include "input.h"
#include "prompt.h"
#include "settings.h"
#include "mb/pg_wchar.h"
-
+#include "fe_utils/psqlscan_int.h"
/* callback functions for our flex lexer */
const PsqlScanCallbacks psqlscan_callbacks = {
@@ -23,6 +24,22 @@ const PsqlScanCallbacks psqlscan_callbacks = {
psql_error
};
+/*
+ * execute query if branch is active.
+ * warn interactive users about ignored queries.
+ */
+static
+bool send_query(const char *query, ConditionalStack cstack)
+{
+ /* execute query if branch is active */
+ if (conditional_active(cstack))
+ return SendQuery(query);
+
+ if (pset.cur_cmd_interactive)
+ psql_error("query ignored, use \\endif or Ctrl-C to exit current branch.\n");
+
+ return true;
+}
/*
* Main processing loop for reading lines of input
@@ -50,6 +67,7 @@ MainLoop(FILE *source)
volatile promptStatus_t prompt_status = PROMPT_READY;
volatile int count_eof = 0;
volatile bool die_on_error = false;
+ ConditionalStack cond_stack;
/* Save the prior command source */
FILE *prev_cmd_source;
@@ -69,6 +87,7 @@ MainLoop(FILE *source)
/* Create working state */
scan_state = psql_scan_create(&psqlscan_callbacks);
+ cond_stack = conditional_stack_create();
query_buf = createPQExpBuffer();
previous_buf = createPQExpBuffer();
@@ -122,7 +141,18 @@ MainLoop(FILE *source)
cancel_pressed = false;
if (pset.cur_cmd_interactive)
+ {
putc('\n', stdout);
+ /*
+ * if interactive user is in a branch, then Ctrl-C will exit
+ * from the inner-most branch
+ */
+ if (!conditional_stack_empty(cond_stack))
+ {
+ psql_error("\\if: escaped\n");
+ conditional_stack_pop(cond_stack);
+ }
+ }
else
{
successResult = EXIT_USER;
@@ -140,7 +170,7 @@ MainLoop(FILE *source)
/* May need to reset prompt, eg after \r command */
if (query_buf->len == 0)
prompt_status = PROMPT_READY;
- line = gets_interactive(get_prompt(prompt_status), query_buf);
+ line = gets_interactive(get_prompt(prompt_status,cond_stack), query_buf);
}
else
{
@@ -296,8 +326,8 @@ MainLoop(FILE *source)
line_saved_in_history = true;
}
- /* execute query */
- success = SendQuery(query_buf->data);
+ success = send_query(query_buf->data,cond_stack);
+
slashCmdStatus = success ? PSQL_CMD_SEND : PSQL_CMD_ERROR;
pset.stmt_lineno = 1;
@@ -343,6 +373,7 @@ MainLoop(FILE *source)
/* execute backslash command */
slashCmdStatus = HandleSlashCmds(scan_state,
+ cond_stack,
query_buf->len > 0 ?
query_buf : previous_buf);
@@ -358,7 +389,7 @@ MainLoop(FILE *source)
if (slashCmdStatus == PSQL_CMD_SEND)
{
- success = SendQuery(query_buf->data);
+ success = send_query(query_buf->data,cond_stack);
/* transfer query to previous_buf by pointer-swapping */
{
@@ -367,6 +398,7 @@ MainLoop(FILE *source)
previous_buf = query_buf;
query_buf = swap_buf;
}
+
resetPQExpBuffer(query_buf);
/* flush any paren nesting info after forced send */
@@ -429,8 +461,7 @@ MainLoop(FILE *source)
if (pset.cur_cmd_interactive)
pg_send_history(history_buf);
- /* execute query */
- success = SendQuery(query_buf->data);
+ success = send_query(query_buf->data,cond_stack);
if (!success && die_on_error)
successResult = EXIT_USER;
@@ -451,7 +482,21 @@ MainLoop(FILE *source)
destroyPQExpBuffer(previous_buf);
destroyPQExpBuffer(history_buf);
+ /*
+ * check for unbalanced \if-\endifs unless user explicitly quit,
+ * or the script is erroring out
+ */
+ if (slashCmdStatus != PSQL_CMD_TERMINATE
+ && successResult != EXIT_USER
+ && !conditional_stack_empty(cond_stack))
+ {
+ psql_error("found EOF before closing \\endif(s)\n");
+ if (die_on_error && !pset.cur_cmd_interactive)
+ successResult = EXIT_USER;
+ }
+
psql_scan_destroy(scan_state);
+ conditional_stack_destroy(cond_stack);
pset.cur_cmd_source = prev_cmd_source;
pset.cur_cmd_interactive = prev_cmd_interactive;
diff --git a/src/bin/psql/prompt.c b/src/bin/psql/prompt.c
index f7930c4..e502ff3 100644
--- a/src/bin/psql/prompt.c
+++ b/src/bin/psql/prompt.c
@@ -66,7 +66,7 @@
*/
char *
-get_prompt(promptStatus_t status)
+get_prompt(promptStatus_t status, ConditionalStack cstack)
{
#define MAX_PROMPT_SIZE 256
static char destination[MAX_PROMPT_SIZE + 1];
@@ -188,7 +188,9 @@ get_prompt(promptStatus_t status)
switch (status)
{
case PROMPT_READY:
- if (!pset.db)
+ if (cstack != NULL && !conditional_active(cstack))
+ buf[0] = '@';
+ else if (!pset.db)
buf[0] = '!';
else if (!pset.singleline)
buf[0] = '=';
diff --git a/src/bin/psql/prompt.h b/src/bin/psql/prompt.h
index 977e754..b3d2d98 100644
--- a/src/bin/psql/prompt.h
+++ b/src/bin/psql/prompt.h
@@ -10,7 +10,8 @@
/* enum promptStatus_t is now defined by psqlscan.h */
#include "fe_utils/psqlscan.h"
+#include "conditional.h"
-char *get_prompt(promptStatus_t status);
+char *get_prompt(promptStatus_t status, ConditionalStack cstack);
#endif /* PROMPT_H */
diff --git a/src/bin/psql/startup.c b/src/bin/psql/startup.c
index 88d686a..02be63e 100644
--- a/src/bin/psql/startup.c
+++ b/src/bin/psql/startup.c
@@ -335,19 +335,24 @@ main(int argc, char *argv[])
else if (cell->action == ACT_SINGLE_SLASH)
{
PsqlScanState scan_state;
+ ConditionalStack cond_stack;
if (pset.echo == PSQL_ECHO_ALL)
puts(cell->val);
scan_state = psql_scan_create(&psqlscan_callbacks);
+ cond_stack = conditional_stack_create();
psql_scan_setup(scan_state,
cell->val, strlen(cell->val),
pset.encoding, standard_strings());
- successResult = HandleSlashCmds(scan_state, NULL) != PSQL_CMD_ERROR
+ successResult = HandleSlashCmds(scan_state,
+ cond_stack,
+ NULL) != PSQL_CMD_ERROR
? EXIT_SUCCESS : EXIT_FAILURE;
psql_scan_destroy(scan_state);
+ conditional_stack_destroy(cond_stack);
}
else if (cell->action == ACT_FILE)
{
diff --git a/src/test/regress/expected/psql.out b/src/test/regress/expected/psql.out
index 026a4f0..2c56e3f 100644
--- a/src/test/regress/expected/psql.out
+++ b/src/test/regress/expected/psql.out
@@ -2712,6 +2712,86 @@ deallocate q;
\pset format aligned
\pset expanded off
\pset border 1
+-- test a large nested if using a variety of true-equivalents
+\if true
+ \if 1
+ \if yes
+ \if on
+ \echo 'all true'
+all true
+ \else
+ \echo 'should not print #1-1'
+ \endif
+ \else
+ \echo 'should not print #1-2'
+ \endif
+ \else
+ \echo 'should not print #1-3'
+ \endif
+\else
+ \echo 'should not print #1-4'
+\endif
+-- test a variety of false-equivalents in an if/elif/else structure
+\if false
+ \echo 'should not print #2-1'
+\elif 0
+ \echo 'should not print #2-2'
+\elif no
+ \echo 'should not print #2-3'
+\elif off
+ \echo 'should not print #2-4'
+\else
+ \echo 'all false'
+all false
+\endif
+-- test simple true-then-else
+\if true
+ \echo 'first thing true'
+first thing true
+\else
+ \echo 'should not print #3-1'
+\endif
+-- test simple false-true-else
+\if false
+ \echo 'should not print #4-1'
+\elif true
+ \echo 'second thing true'
+second thing true
+\else
+ \echo 'should not print #5-1'
+\endif
+-- invalid boolean expressions mean the \if is ignored
+\if invalid_boolean_expression
+unrecognized value "invalid_boolean_expression" for "\if ": boolean expected
+ \echo 'will print anyway #6-1'
+will print anyway #6-1
+\else
+\else: no matching \if
+ \echo 'will print anyway #6-2'
+will print anyway #6-2
+\endif
+\endif: no matching \if
+-- test un-matched endif
+\endif
+\endif: no matching \if
+-- test un-matched else
+\else
+\else: no matching \if
+-- test un-matched elif
+\elif
+\elif: no matching \if
+-- test double-else error
+\if true
+\else
+\else
+\else: cannot occur after \else
+\endif
+-- test elif out-of-order
+\if false
+\else
+\elif
+\elif: cannot occur after \else
+\endif
-- SHOW_CONTEXT
\set SHOW_CONTEXT never
do $$
diff --git a/src/test/regress/sql/psql.sql b/src/test/regress/sql/psql.sql
index d823d11..69fc57c 100644
--- a/src/test/regress/sql/psql.sql
+++ b/src/test/regress/sql/psql.sql
@@ -375,6 +375,82 @@ deallocate q;
\pset expanded off
\pset border 1
+-- test a large nested if using a variety of true-equivalents
+\if true
+ \if 1
+ \if yes
+ \if on
+ \echo 'all true'
+ \else
+ \echo 'should not print #1-1'
+ \endif
+ \else
+ \echo 'should not print #1-2'
+ \endif
+ \else
+ \echo 'should not print #1-3'
+ \endif
+\else
+ \echo 'should not print #1-4'
+\endif
+
+-- test a variety of false-equivalents in an if/elif/else structure
+\if false
+ \echo 'should not print #2-1'
+\elif 0
+ \echo 'should not print #2-2'
+\elif no
+ \echo 'should not print #2-3'
+\elif off
+ \echo 'should not print #2-4'
+\else
+ \echo 'all false'
+\endif
+
+-- test simple true-then-else
+\if true
+ \echo 'first thing true'
+\else
+ \echo 'should not print #3-1'
+\endif
+
+-- test simple false-true-else
+\if false
+ \echo 'should not print #4-1'
+\elif true
+ \echo 'second thing true'
+\else
+ \echo 'should not print #5-1'
+\endif
+
+-- invalid boolean expressions mean the \if is ignored
+\if invalid_boolean_expression
+ \echo 'will print anyway #6-1'
+\else
+ \echo 'will print anyway #6-2'
+\endif
+
+-- test un-matched endif
+\endif
+
+-- test un-matched else
+\else
+
+-- test un-matched elif
+\elif
+
+-- test double-else error
+\if true
+\else
+\else
+\endif
+
+-- test elif out-of-order
+\if false
+\else
+\elif
+\endif
+
-- SHOW_CONTEXT
\set SHOW_CONTEXT never