[tarantool-patches] [PATCH v2 1/1] box: update collation strength option.

[imeevma@tarantool.org]

At the moment all collations that don't have their "strength"
option set works the same way as ones with this option set to
"identical". It is not efficient, according to ICU Comparison
Levels. This patch updates this option of old collations and set
its default value to "primary" for new ones.

Closes #3573
---
Branch: https://github.com/tarantool/tarantool/tree/imeevma/gh-3573-fix-collation-strength
Issue: https://github.com/tarantool/tarantool/issues/3573

 src/box/bootstrap.snap       | Bin 1888 -> 1886 bytes
 src/box/coll_id_def.c        |   4 +-
 src/box/lua/upgrade.lua      |  29 ++++++++++++++-
 src/coll.c                   |  33 ++++++++--------
 src/coll_def.c               |   1 -
 src/coll_def.h               |   3 +-
 test/box-py/bootstrap.result |   2 +-
 test/box/ddl.result          |   6 +--
 test/box/tree_pk.result      |   2 +-
 test/box/tree_pk.test.lua    |   2 +-
 test/sql/collation.result    |  87 +++++++++++++++++++++++++++++++++++++++++++
 test/sql/collation.test.lua  |  32 ++++++++++++++++
 test/unit/coll.cpp           |   2 +
 13 files changed, 176 insertions(+), 27 deletions(-)

diff --git a/src/box/bootstrap.snap b/src/box/bootstrap.snap
index 65739384a66d6ba4a538553ccf4677536ba15280..84b27c0d8b9d6d683692e2ef55034ffcc68d11d0 100644
GIT binary patch
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diff --git a/src/box/coll_id_def.c b/src/box/coll_id_def.c
index 9fe0cda..43f3b63 100644
--- a/src/box/coll_id_def.c
+++ b/src/box/coll_id_def.c
@@ -55,8 +55,8 @@ icu_case_first_from_str(const char *str, uint32_t len)
 static int64_t
 icu_strength_from_str(const char *str, uint32_t len)
 {
-	return strnindex(coll_icu_strength_strs + 1, str, len,
-			 coll_icu_strength_MAX - 1) + 1;
+	return strnindex(coll_icu_strength_strs, str, len,
+			 coll_icu_strength_MAX);
 }
 
 const struct opt_def coll_icu_opts_reg[] = {
diff --git a/src/box/lua/upgrade.lua b/src/box/lua/upgrade.lua
index d9c2ae4..07cace0 100644
--- a/src/box/lua/upgrade.lua
+++ b/src/box/lua/upgrade.lua
@@ -578,6 +578,32 @@ local function upgrade_to_2_1_0()
     box.space._schema:format(format)
 end
 
+--------------------------------------------------------------------------------
+-- Tarantool 2.1.1
+--------------------------------------------------------------------------------
+
+function update_collation_strength_field()
+    local _collation = box.space[box.schema.COLLATION_ID]
+    local _format = _collation:format()
+    for _, collation in ipairs(_collation:select()) do
+        if (collation.opts.strength == nil) then
+            local old_collation = _collation:get{collation.id}
+            local new_collation = {}
+            for _,field in ipairs(_format) do
+                new_collation[field.name] = old_collation[field.name]
+            end
+            new_collation.opts.strength = 'identical'
+            _collation:delete{old_collation.id}
+            _collation:insert(_collation:frommap(new_collation))
+        end
+    end
+end
+
+local function upgrade_to_2_1_1()
+    update_collation_strength_field()
+end
+
+
 local function get_version()
     local version = box.space._schema:get{'version'}
     if version == nil then
@@ -605,7 +631,8 @@ local function upgrade(options)
         {version = mkversion(1, 7, 7), func = upgrade_to_1_7_7, auto = true},
         {version = mkversion(1, 10, 0), func = upgrade_to_1_10_0, auto = true},
         {version = mkversion(1, 10, 2), func = upgrade_to_1_10_2, auto = true},
-        {version = mkversion(2, 1, 0), func = upgrade_to_2_1_0, auto = true}
+        {version = mkversion(2, 1, 0), func = upgrade_to_2_1_0, auto = true},
+        {version = mkversion(2, 1, 1), func = upgrade_to_2_1_1, auto = true}
     }
 
     for _, handler in ipairs(handlers) do
diff --git a/src/coll.c b/src/coll.c
index 6a76f1f..9b719f2 100644
--- a/src/coll.c
+++ b/src/coll.c
@@ -193,22 +193,25 @@ coll_icu_init_cmp(struct coll *coll, const struct coll_def *def)
 			return -1;
 		}
 	}
-	if (def->icu.strength != COLL_ICU_STRENGTH_DEFAULT) {
-		enum coll_icu_strength w = def->icu.strength;
-		UColAttributeValue v =
-			w == COLL_ICU_STRENGTH_PRIMARY ? UCOL_PRIMARY :
-			w == COLL_ICU_STRENGTH_SECONDARY ? UCOL_SECONDARY :
-			w == COLL_ICU_STRENGTH_TERTIARY ? UCOL_TERTIARY :
-			w == COLL_ICU_STRENGTH_QUATERNARY ? UCOL_QUATERNARY :
-			w == COLL_ICU_STRENGTH_IDENTICAL ? UCOL_IDENTICAL :
-			UCOL_DEFAULT;
-		ucol_setAttribute(collator, UCOL_STRENGTH, v, &status);
-		if (U_FAILURE(status)) {
-			diag_set(CollationError, "failed to set strength: %s",
-				 u_errorName(status));
-			return -1;
-		}
+	/*
+	 * Set "strength" option of collation. Default values is
+	 * "primary".
+	 */
+	enum coll_icu_strength w = def->icu.strength;
+	UColAttributeValue v =
+		w == COLL_ICU_STRENGTH_PRIMARY ? UCOL_PRIMARY :
+		w == COLL_ICU_STRENGTH_SECONDARY ? UCOL_SECONDARY :
+		w == COLL_ICU_STRENGTH_TERTIARY ? UCOL_TERTIARY :
+		w == COLL_ICU_STRENGTH_QUATERNARY ? UCOL_QUATERNARY :
+		w == COLL_ICU_STRENGTH_IDENTICAL ? UCOL_IDENTICAL :
+		UCOL_DEFAULT;
+	ucol_setAttribute(collator, UCOL_STRENGTH, v, &status);
+	if (U_FAILURE(status)) {
+		diag_set(CollationError, "failed to set strength: %s",
+			 u_errorName(status));
+		return -1;
 	}
+
 	if (def->icu.numeric_collation != COLL_ICU_DEFAULT) {
 		enum coll_icu_on_off w = def->icu.numeric_collation;
 		UColAttributeValue v = w == COLL_ICU_ON ? UCOL_ON :
diff --git a/src/coll_def.c b/src/coll_def.c
index df58cac..1323643 100644
--- a/src/coll_def.c
+++ b/src/coll_def.c
@@ -54,7 +54,6 @@ const char *coll_icu_case_first_strs[] = {
 };
 
 const char *coll_icu_strength_strs[] = {
-	"DEFAULT",
 	"PRIMARY",
 	"SECONDARY",
 	"TERTIARY",
diff --git a/src/coll_def.h b/src/coll_def.h
index 7c20abf..2a1cb68 100644
--- a/src/coll_def.h
+++ b/src/coll_def.h
@@ -84,8 +84,7 @@ extern const char *coll_icu_case_first_strs[];
 
 /** Strength ICU settings */
 enum coll_icu_strength {
-	COLL_ICU_STRENGTH_DEFAULT = 0,
-	COLL_ICU_STRENGTH_PRIMARY,
+	COLL_ICU_STRENGTH_PRIMARY = 0,
 	COLL_ICU_STRENGTH_SECONDARY,
 	COLL_ICU_STRENGTH_TERTIARY,
 	COLL_ICU_STRENGTH_QUATERNARY,
diff --git a/test/box-py/bootstrap.result b/test/box-py/bootstrap.result
index 506aca3..2532b70 100644
--- a/test/box-py/bootstrap.result
+++ b/test/box-py/bootstrap.result
@@ -5,7 +5,7 @@ box.space._schema:select{}
 ---
 - - ['cluster', '<cluster uuid>']
   - ['max_id', 511]
-  - ['version', 2, 1, 0]
+  - ['version', 2, 1, 1]
 ...
 box.space._cluster:select{}
 ---
diff --git a/test/box/ddl.result b/test/box/ddl.result
index c9a8e96..396318f 100644
--- a/test/box/ddl.result
+++ b/test/box/ddl.result
@@ -484,14 +484,14 @@ box.space._collation:auto_increment{'test', 0, 'ICU', 'ru_RU', setmap{}}
 ...
 box.space._collation:select{}
 ---
-- - [1, 'unicode', 1, 'ICU', '', {}]
+- - [1, 'unicode', 1, 'ICU', '', {'strength': 'identical'}]
   - [2, 'unicode_ci', 1, 'ICU', '', {'strength': 'primary'}]
   - [3, 'test', 0, 'ICU', 'ru_RU', {}]
 ...
 test_run:cmd('restart server default')
 box.space._collation:select{}
 ---
-- - [1, 'unicode', 1, 'ICU', '', {}]
+- - [1, 'unicode', 1, 'ICU', '', {'strength': 'identical'}]
   - [2, 'unicode_ci', 1, 'ICU', '', {'strength': 'primary'}]
   - [3, 'test', 0, 'ICU', 'ru_RU', {}]
 ...
@@ -512,7 +512,7 @@ utf8.cmp('abc', 'def')
 ...
 box.space._collation:replace(t)
 ---
-- [1, 'unicode', 1, 'ICU', '', {}]
+- [1, 'unicode', 1, 'ICU', '', {'strength': 'identical'}]
 ...
 --
 -- gh-2839: allow to store custom fields in field definition.
diff --git a/test/box/tree_pk.result b/test/box/tree_pk.result
index df3c78b..7366ed8 100644
--- a/test/box/tree_pk.result
+++ b/test/box/tree_pk.result
@@ -690,7 +690,7 @@ s:drop()
 ...
 --https://github.com/tarantool/tarantool/issues/2649
 -- create standart index and alter it to collation index
-box.internal.collation.create('test', 'ICU', 'ru-RU')
+box.internal.collation.create('test', 'ICU', 'ru-RU', {strength = 'identical'})
 ---
 ...
 box.internal.collation.create('test-ci', 'ICU', 'ru-RU', {strength = 'secondary'})
diff --git a/test/box/tree_pk.test.lua b/test/box/tree_pk.test.lua
index 1190ab4..b4ee65c 100644
--- a/test/box/tree_pk.test.lua
+++ b/test/box/tree_pk.test.lua
@@ -238,7 +238,7 @@ s:drop()
 
 --https://github.com/tarantool/tarantool/issues/2649
 -- create standart index and alter it to collation index
-box.internal.collation.create('test', 'ICU', 'ru-RU')
+box.internal.collation.create('test', 'ICU', 'ru-RU', {strength = 'identical'})
 box.internal.collation.create('test-ci', 'ICU', 'ru-RU', {strength = 'secondary'})
 s = box.schema.space.create('test')
 i1 = s:create_index('i1', { type = 'tree', parts = {{1, 'str'}}, unique = true })
diff --git a/test/sql/collation.result b/test/sql/collation.result
index 79ba9ab..3c53be1 100644
--- a/test/sql/collation.result
+++ b/test/sql/collation.result
@@ -110,3 +110,90 @@ cn:close()
 box.schema.user.revoke('guest', 'read,write,execute', 'universe')
 ---
 ...
+--
+-- gh-3573: Strength in the _collation space
+-- Collation without 'strength' option set now works as one with
+-- 'strength' set to 'primary'.
+--
+box.internal.collation.create('c0', 'ICU', 'unicode')
+---
+...
+box.internal.collation.create('c1', 'ICU', 'unicode', {strength='primary'})
+---
+...
+box.internal.collation.create('c2', 'ICU', 'unicode', {strength='secondary'})
+---
+...
+box.internal.collation.create('c5', 'ICU', 'unicode', {strength='identical'})
+---
+...
+box.sql.execute([[create table tc (id int primary key autoincrement, s0 string collate "c0", s1 string collate "c1", s2 string collate "c2", s5 string collate "c5")]])
+---
+...
+box.sql.execute([[insert into tc values (null, 'a', 'a', 'a', 'a')]])
+---
+...
+box.sql.execute([[insert into tc values (null, 'A', 'A', 'A', 'A')]])
+---
+...
+box.sql.execute([[insert into tc values (null, 'á', 'á', 'á', 'á')]])
+---
+...
+box.sql.execute([[insert into tc values (null, 'â', 'â', 'â', 'â')]])
+---
+...
+box.sql.execute([[select * from tc where s0 = 'a']])
+---
+- - [1, 'a', 'a', 'a', 'a']
+  - [2, 'A', 'A', 'A', 'A']
+  - [3, 'á', 'á', 'á', 'á']
+  - [4, 'â', 'â', 'â', 'â']
+...
+box.sql.execute([[select * from tc where s1 = 'a']])
+---
+- - [1, 'a', 'a', 'a', 'a']
+  - [2, 'A', 'A', 'A', 'A']
+  - [3, 'á', 'á', 'á', 'á']
+  - [4, 'â', 'â', 'â', 'â']
+...
+box.sql.execute([[select * from tc where s2 = 'a']])
+---
+- - [1, 'a', 'a', 'a', 'a']
+  - [2, 'A', 'A', 'A', 'A']
+...
+box.sql.execute([[select * from tc where s5 = 'a']])
+---
+- - [1, 'a', 'a', 'a', 'a']
+...
+a = box.sql.execute([[select id from tc where s0 = 'a']])
+---
+...
+b = box.sql.execute([[select id from tc where s1 = 'a']])
+---
+...
+count = 0
+---
+...
+for k,v in pairs(a) do if (a[k][1] ~= b[k][1]) then count = count + 1 end end
+---
+...
+-- Should be true as default value is 'primary'.
+count == 0
+---
+- true
+...
+box.sql.execute([[drop table tc]])
+---
+...
+box.internal.collation.drop('c0')
+---
+...
+box.internal.collation.drop('c1')
+---
+...
+box.internal.collation.drop('c2')
+---
+...
+box.internal.collation.drop('c5')
+---
+...
diff --git a/test/sql/collation.test.lua b/test/sql/collation.test.lua
index 935dea8..1923503 100644
--- a/test/sql/collation.test.lua
+++ b/test/sql/collation.test.lua
@@ -43,3 +43,35 @@ cn:execute('select 1 limit ? collate not_exist', {1})
 
 cn:close()
 box.schema.user.revoke('guest', 'read,write,execute', 'universe')
+
+--
+-- gh-3573: Strength in the _collation space
+-- Collation without 'strength' option set now works as one with
+-- 'strength' set to 'primary'.
+--
+box.internal.collation.create('c0', 'ICU', 'unicode')
+box.internal.collation.create('c1', 'ICU', 'unicode', {strength='primary'})
+box.internal.collation.create('c2', 'ICU', 'unicode', {strength='secondary'})
+box.internal.collation.create('c5', 'ICU', 'unicode', {strength='identical'})
+box.sql.execute([[create table tc (id int primary key autoincrement, s0 string collate "c0", s1 string collate "c1", s2 string collate "c2", s5 string collate "c5")]])
+box.sql.execute([[insert into tc values (null, 'a', 'a', 'a', 'a')]])
+box.sql.execute([[insert into tc values (null, 'A', 'A', 'A', 'A')]])
+box.sql.execute([[insert into tc values (null, 'á', 'á', 'á', 'á')]])
+box.sql.execute([[insert into tc values (null, 'â', 'â', 'â', 'â')]])
+box.sql.execute([[select * from tc where s0 = 'a']])
+box.sql.execute([[select * from tc where s1 = 'a']])
+box.sql.execute([[select * from tc where s2 = 'a']])
+box.sql.execute([[select * from tc where s5 = 'a']])
+a = box.sql.execute([[select id from tc where s0 = 'a']])
+b = box.sql.execute([[select id from tc where s1 = 'a']])
+count = 0
+for k,v in pairs(a) do if (a[k][1] ~= b[k][1]) then count = count + 1 end end
+
+-- Should be true as default value is 'primary'.
+count == 0
+
+box.sql.execute([[drop table tc]])
+box.internal.collation.drop('c0')
+box.internal.collation.drop('c1')
+box.internal.collation.drop('c2')
+box.internal.collation.drop('c5')
diff --git a/test/unit/coll.cpp b/test/unit/coll.cpp
index 94374a7..acbc7f4 100644
--- a/test/unit/coll.cpp
+++ b/test/unit/coll.cpp
@@ -51,6 +51,7 @@ manual_test()
 	memset(&def, 0, sizeof(def));
 	snprintf(def.locale, sizeof(def.locale), "%s", "ru_RU");
 	def.type = COLL_TYPE_ICU;
+	def.icu.strength = COLL_ICU_STRENGTH_IDENTICAL;
 	struct coll *coll;
 
 	cout << " -- default ru_RU -- " << endl;
@@ -134,6 +135,7 @@ hash_test()
 	struct coll *coll;
 
 	/* Case sensitive */
+	def.icu.strength = COLL_ICU_STRENGTH_IDENTICAL;
 	coll = coll_new(&def);
 	assert(coll != NULL);
 	cout << "Case sensitive" << endl;
-- 
2.7.4