scan: fix decimal filters precision loss

Before this patch, decimals were cast to numbers in filters through
`tostring` in codegen. This patch fixes this precision loss.

Part of #373

CHANGELOG.md

@@ -10,6 +10,8 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 ### Fixed
 * Working with datetime conditions in case of non-indexed fields or
   non-iterating indexes (#373).
+* Precision loss for decimal conditions in case of non-indexed fields or
+  non-iterating indexes (#373).
 
 ## [1.4.3] - 05-02-24
 

crud/compare/filters.lua

@@ -1,4 +1,5 @@
 local datetime_supported, datetime = pcall(require, 'datetime')
+local decimal_supported, decimal = pcall(require, 'decimal')
 
 local errors = require('errors')
 
@@ -159,6 +160,9 @@ local function format_value(value)
         return tostring(value)
     elseif type(value) == 'boolean' then
         return tostring(value)
+    elseif decimal_supported and decimal.is_decimal(value) then
+        -- decimal supports comparison with string.
+        return ("%q"):format(tostring(value))
     elseif utils.is_uuid(value) then
         return ("%q"):format(value)
     elseif datetime_supported and datetime.is_datetime(value) then

test/entrypoint/srv_select/storage_init.lua

@@ -1,4 +1,5 @@
 local datetime_supported, _ = pcall(require, 'datetime')
+local decimal_supported, _ = pcall(require, 'decimal')
 local crud_utils = require('crud.common.utils')
 
 return function()
@@ -229,6 +230,102 @@ return function()
         if_not_exists = true,
     })
 
+    if decimal_supported then
+        local decimal_format = {
+            {name = 'id', type = 'unsigned'},
+            {name = 'bucket_id', type = 'unsigned'},
+            {name = 'decimal_field', type = 'decimal'},
+        }
+
+
+        local decimal_nonindexed_space = box.schema.space.create('decimal_nonindexed', {
+            if_not_exists = true,
+            engine = engine,
+        })
+
+        decimal_nonindexed_space:format(decimal_format)
+
+        decimal_nonindexed_space:create_index('id_index', {
+            parts = { 'id' },
+            if_not_exists = true,
+        })
+
+        decimal_nonindexed_space:create_index('bucket_id', {
+            parts = { 'bucket_id' },
+            unique = false,
+            if_not_exists = true,
+        })
+
+
+        local decimal_indexed_space = box.schema.space.create('decimal_indexed', {
+            if_not_exists = true,
+            engine = engine,
+        })
+
+        decimal_indexed_space:format(decimal_format)
+
+        decimal_indexed_space:create_index('id_index', {
+            parts = { 'id' },
+            if_not_exists = true,
+        })
+
+        decimal_indexed_space:create_index('bucket_id', {
+            parts = { 'bucket_id' },
+            unique = false,
+            if_not_exists = true,
+        })
+
+        decimal_indexed_space:create_index('decimal_index', {
+            parts = { 'decimal_field' },
+            unique = false,
+            if_not_exists = true,
+        })
+
+
+        local decimal_pk_space = box.schema.space.create('decimal_pk', {
+            if_not_exists = true,
+            engine = engine,
+        })
+
+        decimal_pk_space:format(decimal_format)
+
+        decimal_pk_space:create_index('decimal_index', {
+            parts = { 'decimal_field' },
+            if_not_exists = true,
+        })
+
+        decimal_pk_space:create_index('bucket_id', {
+            parts = { 'bucket_id' },
+            unique = false,
+            if_not_exists = true,
+        })
+
+
+        local decimal_multipart_index_space = box.schema.space.create('decimal_multipart_index', {
+            if_not_exists = true,
+            engine = engine,
+        })
+
+        decimal_multipart_index_space:format(decimal_format)
+
+        decimal_multipart_index_space:create_index('id_index', {
+            parts = { 'id' },
+            if_not_exists = true,
+        })
+
+        decimal_multipart_index_space:create_index('bucket_id', {
+            parts = { 'bucket_id' },
+            unique = false,
+            if_not_exists = true,
+        })
+
+        decimal_multipart_index_space:create_index('decimal_index', {
+            parts = { 'id', 'decimal_field' },
+            unique = false,
+            if_not_exists = true,
+        })
+    end
+
     if datetime_supported then
         local datetime_format = {
             {name = 'id', type = 'unsigned'},

test/helper.lua

@@ -958,9 +958,32 @@ function helpers.prepare_ordered_data(g, space, expected_objects, bucket_id, ord
     t.assert_equals(objects, expected_objects)
 end
 
+function helpers.skip_decimal_unsupported()
+    local module_available, _ = pcall(require, 'decimal')
+    t.skip_if(not module_available, 'decimal is not supported')
+end
+
 function helpers.skip_datetime_unsupported()
     local module_available, _ = pcall(require, 'datetime')
     t.skip_if(not module_available, 'datetime is not supported')
 end
 
+function helpers.merge_tables(t1, t2, ...)
+    if t2 == nil then
+        return t1
+    end
+
+    local res = {}
+
+    for k, v in pairs(t1) do
+        res[k] = v
+    end
+
+    for k, v in pairs(t2) do
+        res[k] = v
+    end
+
+    return helpers.merge_tables(res, ...)
+end
+
 return helpers

test/integration/count_test.lua

@@ -883,7 +883,12 @@ pgroup.test_gh_418_count_with_secondary_noneq_index_condition = function(g)
     read_scenario.gh_418_read_with_secondary_noneq_index_condition(g, read_impl)
 end
 
-for case_name_template, case in pairs(read_scenario.gh_373_read_with_datetime_condition_cases) do
+local gh_373_types_cases = helpers.merge_tables(
+    read_scenario.gh_373_read_with_decimal_condition_cases,
+    read_scenario.gh_373_read_with_datetime_condition_cases
+)
+
+for case_name_template, case in pairs(gh_373_types_cases) do
     local case_name = 'test_' .. case_name_template:format('count')
 
     pgroup[case_name] = function(g)

test/integration/pairs_readview_test.lua

@@ -907,7 +907,12 @@ pgroup.test_gh_418_pairs_with_secondary_noneq_index_condition = function(g)
     read_scenario.gh_418_read_with_secondary_noneq_index_condition(g, read_impl)
 end
 
-for case_name_template, case in pairs(read_scenario.gh_373_read_with_datetime_condition_cases) do
+local gh_373_types_cases = helpers.merge_tables(
+    read_scenario.gh_373_read_with_decimal_condition_cases,
+    read_scenario.gh_373_read_with_datetime_condition_cases
+)
+
+for case_name_template, case in pairs(gh_373_types_cases) do
     local case_name = 'test_' .. case_name_template:format('pairs')
 
     pgroup[case_name] = function(g)

test/integration/pairs_test.lua

@@ -915,7 +915,12 @@ pgroup.test_gh_418_pairs_with_secondary_noneq_index_condition = function(g)
     read_scenario.gh_418_read_with_secondary_noneq_index_condition(g, read_impl)
 end
 
-for case_name_template, case in pairs(read_scenario.gh_373_read_with_datetime_condition_cases) do
+local gh_373_types_cases = helpers.merge_tables(
+    read_scenario.gh_373_read_with_decimal_condition_cases,
+    read_scenario.gh_373_read_with_datetime_condition_cases
+)
+
+for case_name_template, case in pairs(gh_373_types_cases) do
     local case_name = 'test_' .. case_name_template:format('pairs')
 
     pgroup[case_name] = function(g)