fix(DataStore): QueryPredicate translation

[618coffee]

Issue #, if available:
A fix for issue: #907

Description of changes:
The previous translation from QueryPredicate to sql statement is incorrect

For example:
If I have a predicate like

let predicate = (todo.name == "name2" && todo.tag == "optional") || todo.description == "wake up"

SQL statement generated by the incorrect code is:

select
  "root"."id" as "id", "root"."description" as "description", "root"."name" as "name",
  "root"."tag" as "tag"
from Todo as "root"
where 1 = 1
  and (
    or (
      "root"."name" = ?
      and "root"."tag" = ?
    )
    and "root"."description" = ?
  )

which fails DataStore.query()

The correct one should be:

select
  "root"."id" as "id", "root"."description" as "description", "root"."name" as "name",
  "root"."tag" as "tag"
from Todo as "root"
where 1 = 1
  and (
    (
      "root"."name" = ?
      and "root"."tag" = ?
    )
    or "root"."description" = ?
  )

My PR update the implementation of ConditionStatement generation
By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[codecov]

Codecov Report

Merging #961 (16379d0) into main (6fb4841) will increase coverage by 0.10%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main     #961      +/-   ##
==========================================
+ Coverage   70.39%   70.50%   +0.10%     
==========================================
  Files         920      920              
  Lines       39049    39194     +145     
==========================================
+ Hits        27490    27632     +142     
- Misses      11559    11562       +3     

Flag	Coverage Δ
API_plugin_unit_test	64.02% <ø> (-0.08%)	⬇️
Analytics_plugin_unit_test	72.38% <ø> (ø)
Auth_plugin_unit_test	75.13% <ø> (ø)
DataStore_plugin_unit_test	83.90% <100.00%> (+0.21%)	⬆️
Predictions_plugin_unit_test	50.43% <ø> (ø)
Storage_plugin_unit_test	74.74% <ø> (ø)
build_test_amplify	62.38% <ø> (-0.02%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
...Plugin/Storage/SQLite/SQLStatement+Condition.swift	100.00% <100.00%> (ø)
...reCategoryPluginTests/Core/SQLStatementTests.swift	100.00% <100.00%> (ø)
...lugin/Operation/AWSAPIOperation+APIOperation.swift	78.37% <0.00%> (-5.41%)	⬇️
.../DataStore/Model/Internal/Schema/ModelSchema.swift	85.29% <0.00%> (-2.95%)	⬇️
...Hub/DefaultPluginTests/DefaultHubPluginTests.swift	87.20% <0.00%> (-1.17%)	⬇️
...s/AWSHubPlugin/Internal/HubChannelDispatcher.swift	97.05% <0.00%> (+2.94%)	⬆️

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[618coffee]

• opAhead: decide whether and or or operator should be added before bracket depends on

• groupType: the operation applied to two QueryPredicateOperation.

[lawmicha]

if you have to explain the variable name here then consider renaming the variable and refactor as you try to rename it. If the variable still needs some explanation, then better add some documentation to the top of the function

[wooj2]

Looking at the android implementation, it looks pretty elegant:
https://github.com/aws-amplify/amplify-android/blob/fef0cc31b50c427c60e144346a896c20a2f440e4/aws-datastore/src/main/java/com/amplifyframework/datastore/storage/sqlite/adapter/SQLPredicate.java#L108

Maybe we can get some inspiration from their codebase?

[lawmicha]

any tests at the unit test or integration test level that would run against a real SQL store to ensure the issue is fixed ?

[lawmicha]

you could also have default parameter values as -1 and .and for the translate method and comment on top why the default values are used. or add the comment on top here

[618coffee]

added some descriptive words

[618coffee]

Added one integration test

[lawmicha]

LGTM