Improve uninitialised variable analysis for statements with on-fail

[pcnfernando]

Purpose

$subject
Fixes #38530

Approach

Describe how you are implementing the solutions along with the design details.

Samples

Provide high-level details about the samples related to this feature.

Remarks

List any other known issues, related PRs, TODO items, or any other notes related to the PR.

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

[KavinduZoysa]

import ballerina/io;
public function main() returns error? {
    int i;
    do {
        // check error("error");
        var _ = object {
            function init() {
                i = 2;
                io:println("222");
            }
        };
    } on fail {
        io:println("on fail");
    }
    io:println(i);
}

Please check this example. The expected output is not clear.

[codecov]

Codecov Report

Patch coverage: 97.18% and project coverage change: +76.41% 🎉

Comparison is base (8a0431e) 0.00% compared to head (4f33405) 76.41%.
Report is 17 commits behind head on master.

Additional details and impacted files

@@              Coverage Diff              @@
##             master   #40971       +/-   ##
=============================================
+ Coverage      0.00%   76.41%   +76.41%     
- Complexity        0    52146    +52146     
=============================================
  Files             9     2858     +2849     
  Lines            35   196060   +196025     
  Branches          0    25411    +25411     
=============================================
+ Hits              0   149810   +149810     
- Misses           35    37948    +37913     
- Partials          0     8302     +8302     

Files Changed	Coverage Δ
.../compiler/semantics/analyzer/DataflowAnalyzer.java	89.96% <97.18%> (ø)

... and 2856 files with indirect coverage changes

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[pcnfernando]

import ballerina/io;
public function main() returns error? {
    int i;
    do {
        // check error("error");
        var _ = object {
            function init() {
                i = 2;
                io:println("222");
            }
        };
    } on fail {
        io:println("on fail");
    }
    io:println(i);
}

This is not actually related to on-fail

import ballerina/io;

public function main() returns error? {
    int i;
    var _ = object {
        function init() {
            i = 2;
            io:println("222");
        }
    };
    io:println(i); // uninint var error
}

Hence, created #41013

[github-actions]

This PR has been open for more than 15 days with no activity. This will be closed in 3 days unless the stale label is removed or commented.