Fix defaults from the applicable contextually-expected type not being used when a mapping constructor has readonly fields

[MaryamZi]

Purpose

$title.

Fixes #33162

Check List

• Read the Contributing Guide
• Updated Change Log
• Checked Tooling Support (#)
• Added necessary tests
  • Unit Tests
  • Spec Conformance Tests
  • Integration Tests
  • Ballerina By Example Tests
• Increased Test Coverage
• Added necessary documentation
  • API documentation
  • Module documentation in Module.md files
  • Ballerina By Examples

[MaryamZi]

Since it is not possible to call record field default closures individually atm, the fix done for the time-being is adding the original type as an included type to make its init method (that initiates the fields) get called.

However this will cause issues for something like

type Foo record {
    string[] x = ["foo", "bar"];
};

// Panics now with `invalid value for record field 'x': expected value of type 'string[] & readonly', found 'string[]'`,
// since `x` is initialized using the mutable value from `Foo` before the mapping constructor's value.
Foo _ = {readonly x: [""]};

This does not panic in Beta3/Beta4 but will panic with this fix.

Related to #24077 in a way.

type Foo record {
    int[] x = [];
};

Foo & readonly _ = {};

Also panics at runtime atm.

But if we don't fix this, defaults won't be used in cases like

import ballerina/io;

type Foo record {
    int i;
    string s = "default";
};

public function main() {
    Foo f = {readonly i: 1};
    io:println(f); // `{"i":1,"s":null}` and not `{"i":1,"s":"default"}`
}

@hasithaa, thoughts please?

[hasithaa]

+1 for now. will @chiranSachintha fix for closures address this? I guess not.

[MaryamZi]

We need to introduce similar closures for record default values, right? Created #33771 to track fixing it. #32012 also depends on it.

Created #33773 to track fixing this specific case.

[codecov]

Codecov Report

Merging #33767 (72dc954) into master (b7c30a6) will decrease coverage by 0.00%.
The diff coverage is 95.45%.

@@             Coverage Diff              @@
##             master   #33767      +/-   ##
============================================
- Coverage     74.06%   74.05%   -0.01%     
+ Complexity    44670    44666       -4     
============================================
  Files          3130     3130              
  Lines        174290   174302      +12     
  Branches      22453    22454       +1     
============================================
- Hits         129087   129086       -1     
- Misses        37562    37575      +13     
  Partials       7641     7641              

Impacted Files	Coverage Δ
...alang/compiler/semantics/analyzer/TypeChecker.java	87.06% <92.30%> (+0.03%)	⬆️
...llerinalang/compiler/util/ImmutableTypeCloner.java	91.03% <100.00%> (-0.15%)	⬇️
...lerinalang/compiler/util/TypeDefBuilderHelper.java	89.91% <100.00%> (+0.63%)	⬆️
...runtime/internal/scheduling/WorkerDataChannel.java	84.71% <0.00%> (-4.46%)	⬇️
.../ballerina/runtime/internal/scheduling/Strand.java	79.89% <0.00%> (-2.58%)	⬇️
...alang/langserver/diagnostic/DiagnosticsHelper.java	72.91% <0.00%> (-1.05%)	⬇️
.../compiler/bir/codegen/interop/JMethodResolver.java	78.59% <0.00%> (-0.27%)	⬇️
...viders/context/ListenerDeclarationNodeContext.java	74.23% <0.00%> (+0.61%)	⬆️

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