[PATCH v1 1/1] test: check hints corner cases

[Kirill Shcherbatov <kshcherbatov@tarantool.org>]

We must to enshure that hints don't broke tuple comparison.
As different field_types use different routines to calculate hint,
we must to ensure that the calculated values are compatible with
each other.

Also tested the corner cases for large double numbers, due to the
fact that there may be additional difficulties in hint construction.

Follow-up
    9fba29abb4e0 memtx: introduce tuple compare hint
---
 test/engine/hints.result   | 191 +++++++++++++++++++++++++++++++++++++
 test/engine/hints.test.lua |  62 ++++++++++++
 2 files changed, 253 insertions(+)
 create mode 100644 test/engine/hints.result
 create mode 100644 test/engine/hints.test.lua

diff --git a/test/engine/hints.result b/test/engine/hints.result
new file mode 100644
index 000000000..946f82039
--- /dev/null
+++ b/test/engine/hints.result
@@ -0,0 +1,191 @@
+--
+-- gh-3961: Introduce tuple comparison hints
+-- We must to enshure that hints don't broke
+-- tuple comparison.
+--
+ffi = require('ffi')
+---
+...
+test_run = require('test_run')
+---
+...
+inspector = test_run.new()
+---
+...
+engine = inspector:get_cfg('engine')
+---
+...
+inspector:cmd("setopt delimiter ';'");
+---
+- true
+...
+function insert_values(type)
+        local x = 54
+        while (x <= 64) do
+                local val = ffi.new(type, 2^x-1)
+                s:replace({val})
+                x = x + 1
+        end
+end;
+---
+...
+inspector:cmd("setopt delimiter ''");
+---
+- true
+...
+-- Test that hints does not violate the correct order of
+-- big numeric fields.
+s = box.schema.space.create('test', {engine = engine})
+---
+...
+i1 = s:create_index('i1', {parts = {1, 'unsigned'}})
+---
+...
+insert_values('uint64_t')
+---
+...
+s:select()
+---
+- - [0]
+  - [18014398509481984]
+  - [36028797018963968]
+  - [72057594037927936]
+  - [144115188075855872]
+  - [288230376151711744]
+  - [576460752303423488]
+  - [1152921504606846976]
+  - [2305843009213693952]
+  - [4611686018427387904]
+  - [9223372036854775808]
+...
+i1:alter{parts = {1, 'integer'}}
+---
+...
+insert_values('int64_t')
+---
+...
+s:select()
+---
+- - [-9223372036854775808]
+  - [0]
+  - [18014398509481984]
+  - [36028797018963968]
+  - [72057594037927936]
+  - [144115188075855872]
+  - [288230376151711744]
+  - [576460752303423488]
+  - [1152921504606846976]
+  - [2305843009213693952]
+  - [4611686018427387904]
+  - [9223372036854775808]
+...
+i1:alter{parts = {1, 'number'}}
+---
+...
+insert_values('double')
+---
+...
+s:select()
+---
+- - [-9223372036854775808]
+  - [0]
+  - [18014398509481984]
+  - [36028797018963968]
+  - [72057594037927936]
+  - [144115188075855872]
+  - [288230376151711744]
+  - [576460752303423488]
+  - [1152921504606846976]
+  - [2305843009213693952]
+  - [4611686018427387904]
+  - [9223372036854775808]
+  - [1.844674407371e+19]
+...
+s:drop()
+---
+...
+-- Test that the use of hint(s) does not violate alter between
+-- scalar and string.
+s = box.schema.space.create('test', {engine = engine})
+---
+...
+i1 = s:create_index('i1', {parts = {1, 'string'}})
+---
+...
+s:insert({"bbb"})
+---
+- ['bbb']
+...
+s:insert({"ccc"})
+---
+- ['ccc']
+...
+i1:alter{parts = {1, 'scalar'}}
+---
+...
+s:insert({"aaa"})
+---
+- ['aaa']
+...
+s:insert({"ddd"})
+---
+- ['ddd']
+...
+s:select()
+---
+- - ['aaa']
+  - ['bbb']
+  - ['ccc']
+  - ['ddd']
+...
+s:drop()
+---
+...
+-- Test that hints does not violate the correct order of
+-- numeric fields (on alter).
+s = box.schema.space.create('test', {engine = engine})
+---
+...
+i1 = s:create_index('i1', {parts = {1, 'unsigned'}})
+---
+...
+s:insert({11})
+---
+- [11]
+...
+i1:alter{parts = {1, 'integer'}}
+---
+...
+s:insert({-22})
+---
+- [-22]
+...
+i1:alter{parts = {1, 'number'}}
+---
+...
+s:insert({-33.33})
+---
+- [-33.33]
+...
+i1:alter{parts = {1, 'scalar'}}
+---
+...
+s:insert({44.44})
+---
+- [44.44]
+...
+s:insert({"Hello world"})
+---
+- ['Hello world']
+...
+s:select()
+---
+- - [-33.33]
+  - [-22]
+  - [11]
+  - [44.44]
+  - ['Hello world']
+...
+s:drop()
+---
+...
diff --git a/test/engine/hints.test.lua b/test/engine/hints.test.lua
new file mode 100644
index 000000000..266516ec9
--- /dev/null
+++ b/test/engine/hints.test.lua
@@ -0,0 +1,62 @@
+--
+-- gh-3961: Introduce tuple comparison hints
+-- We must to enshure that hints don't broke
+-- tuple comparison.
+--
+ffi = require('ffi')
+
+test_run = require('test_run')
+inspector = test_run.new()
+engine = inspector:get_cfg('engine')
+
+inspector:cmd("setopt delimiter ';'");
+function insert_values(type)
+        local x = 54
+        while (x <= 64) do
+                local val = ffi.new(type, 2^x-1)
+                s:replace({val})
+                x = x + 1
+        end
+end;
+inspector:cmd("setopt delimiter ''");
+
+-- Test that hints does not violate the correct order of
+-- big numeric fields.
+s = box.schema.space.create('test', {engine = engine})
+i1 = s:create_index('i1', {parts = {1, 'unsigned'}})
+insert_values('uint64_t')
+s:select()
+i1:alter{parts = {1, 'integer'}}
+insert_values('int64_t')
+s:select()
+i1:alter{parts = {1, 'number'}}
+insert_values('double')
+s:select()
+s:drop()
+
+-- Test that the use of hint(s) does not violate alter between
+-- scalar and string.
+s = box.schema.space.create('test', {engine = engine})
+i1 = s:create_index('i1', {parts = {1, 'string'}})
+s:insert({"bbb"})
+s:insert({"ccc"})
+i1:alter{parts = {1, 'scalar'}}
+s:insert({"aaa"})
+s:insert({"ddd"})
+s:select()
+s:drop()
+
+-- Test that hints does not violate the correct order of
+-- numeric fields (on alter).
+s = box.schema.space.create('test', {engine = engine})
+i1 = s:create_index('i1', {parts = {1, 'unsigned'}})
+s:insert({11})
+i1:alter{parts = {1, 'integer'}}
+s:insert({-22})
+i1:alter{parts = {1, 'number'}}
+s:insert({-33.33})
+i1:alter{parts = {1, 'scalar'}}
+s:insert({44.44})
+s:insert({"Hello world"})
+s:select()
+s:drop()
-- 
2.21.0