test/interactive: disable hide/show prompt feature

See #7169 for details about the hide/show prompt feature. In short, it
hides readline's prompt before `print()` or `log.<level>()` calls and
restores the prompt afterwards.

This feature sometimes badly interferes with
`test.interactive_tarantool` heuristics about readline's command
echoing.

This commit disables the feature in `test.interactive_tarantool` by
default and enables it explicitly where needed.

Part of #9985

NO_DOC=testing helper change
NO_CHANGELOG=see NO_DOC

(cherry picked from commit 23094b6f)

test/app-luatest/gh_8136_fix_print_wrapper_not_handling_errors_thrown_from_print_test.lua

@@ -5,7 +5,10 @@ local g = t.group()
 
 -- Checks that `print` throwing an error is handled correctly.
 g.test_basic_print_with_exception = function()
-    local child = it.new({args = {'-l', 'fiber'}})
+    local child = it.new({
+        args = {'-l', 'fiber'},
+        env = {TT_CONSOLE_HIDE_SHOW_PROMPT = 'true'},
+    })
 
     child:execute_command([[
         _ = fiber.create(function()

test/box-luatest/gh_8051_set_box_cfg_thru_env_test.lua

-local fun = require('fun')
 local server = require('luatest.server')
 local treegen = require('test.treegen')
 local it = require('test.interactive_tarantool')
@@ -28,13 +27,6 @@ g.after_all(function(g)
     treegen.clean(g)
 end)
 
--- Disable hide/show prompt functionality, because it breaks a
--- command echo check. The reason is that the 'scheduled next
--- checkpoint' log message is issued from a background fiber.
-local env_default = {
-    TT_CONSOLE_HIDE_SHOW_PROMPT = 'false',
-}
-
 g.test_json_table_curly_bracket = function()
     local env = {["TT_METRICS"] = '{"labels":{"alias":"gh_8051"},' ..
                                   '"include":"all","exclude":["vinyl"]}'}
@@ -47,9 +39,9 @@ end
 
 g.test_json_table_square_bracket = function(g)
     g.child = it.new({
-        env = fun.chain(env_default, {
+        env = {
             TT_LISTEN = '["localhost:0"]',
-        }):tomap(),
+        },
     })
 
     local command = ('box.cfg({work_dir = %q})'):format(g.dir)
@@ -70,9 +62,9 @@ end
 
 g.test_format_error = function(g)
     g.child = it.new({
-        env = fun.chain(env_default, {
+        env = {
             TT_LOG_MODULES = 'aaa=info,bbb',
-        }):tomap(),
+        },
     })
 
     local command = ('box.cfg({work_dir = %q})'):format(g.dir)
@@ -82,9 +74,9 @@ end
 
 g.test_format_error_empty_key = function()
     g.child = it.new({
-        env = fun.chain(env_default, {
+        env = {
             TT_LOG_MODULES = 'aaa=info,=error',
-        }):tomap(),
+        },
     })
 
     local command = ('box.cfg({work_dir = %q})'):format(g.dir)

test/box-luatest/hide_show_prompt_test.lua

@@ -8,7 +8,10 @@ local g = t.group()
 -- It does not check that tarantool preserves current input line
 -- and cursor position.
 g.test_basic_print = function()
-    local child = it.new({args = {'-l', 'fiber'}})
+    local child = it.new({
+        args = {'-l', 'fiber'},
+        env = {TT_CONSOLE_HIDE_SHOW_PROMPT = 'true'},
+    })
 
     child:execute_command([[
         _ = fiber.create(function()
@@ -35,7 +38,10 @@ end
 -- We don't check for presence of 'flood' lines in the log, but
 -- verify that prompt on stdout is shown and hid.
 g.test_basic_log = function()
-    local child = it.new({args = {'-l', 'fiber', '-l', 'log'}})
+    local child = it.new({
+        args = {'-l', 'fiber', '-l', 'log'},
+        env = {TT_CONSOLE_HIDE_SHOW_PROMPT = 'true'},
+    })
 
     child:execute_command([[
         _ = fiber.create(function()

test/interactive_tarantool.lua

@@ -333,6 +333,13 @@ function M._new_internal(opts)
             -- (because the command in the echo output will be
             -- trimmed).
             INPUTRC = '/dev/null',
+            -- Disable hide/show prompt functionality, because it
+            -- may break a command echo check.
+            --
+            -- For example, it occurs on the 'scheduled next
+            -- checkpoint' log message, which is issued from a
+            -- background fiber.
+            TT_CONSOLE_HIDE_SHOW_PROMPT = 'false',
         }, env):tomap(),
     })