Restrict logical navigations to the running match in running semantics

[kasiafi]

Description

Before this change, the logical navigation function FIRST could return position out of bounds of the current match in the running semantics. Now it is restricted to the current match.

Additional context and related issues

Fixes: #26981

Release notes

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## General
* In row pattern matching, restrict logical navigations to current match in running semantics. ({issue}`26981`)

Summary by Sourcery

Restrict logical navigation functions to the current match bounds in running semantics and update tests accordingly.

Bug Fixes:

• Prevent FIRST and LAST navigations from returning positions outside the current match in running semantics

Tests:

• Adjust expected results for FIRST navigation to null when the match is not yet complete in running semantics

[sourcery-ai]

Reviewer's guide (collapsed on small PRs)

Reviewer's Guide

Restrict logical FIRST and LAST navigations to the active match when running semantics are enabled by computing a dynamic boundary (patternEndInclusive) and propagating it through navigation methods, and update tests to expect null for out-of-match accesses.

Sequence diagram for restricted logical navigation in running semantics

sequenceDiagram
    participant "resolvePosition()"
    participant "findFirstAndForward()"
    participant "findLastAndBackwards()"
    participant "ArrayView"
    "resolvePosition()"->>"findFirstAndForward()": if !last, pass patternEndInclusive
    "resolvePosition()"->>"findLastAndBackwards()": if last, pass patternEndInclusive
    "findFirstAndForward()"->>"ArrayView": iterate up to patternEndInclusive
    "findLastAndBackwards()"->>"ArrayView": iterate down to 0 from patternEndInclusive
    "resolvePosition()"->>"adjustPosition()": adjust final position

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Class diagram for updated LogicalIndexNavigation methods

classDiagram
    class LogicalIndexNavigation {
        +resolvePosition(currentRow, matchedLabels, searchStart, searchEnd)
        -findLastAndBackwards(patternEndInclusive, matchedLabels)
        -findFirstAndForward(matchedLabels, patternEndInclusive)
    }
    LogicalIndexNavigation : int logicalOffset
    LogicalIndexNavigation : Set<String> labels
    LogicalIndexNavigation : boolean last
    LogicalIndexNavigation : boolean running
    LogicalIndexNavigation : int adjustPosition(relativePosition, patternStart, searchStart, searchEnd)
    LogicalIndexNavigation --> ArrayView
    ArrayView : int length()
    ArrayView : String get(int)

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File-Level Changes

Change	Details	Files
Constrain logical navigation range based on current match	Introduce patternEndInclusive for running semantics bound Refactor findLastAndBackwards and findFirstAndForward to use patternEndInclusive Update navigation loops to prevent out-of-match positions	core/trino-main/src/main/java/io/trino/operator/window/pattern/LogicalIndexNavigation.java
Update tests for restricted navigation behavior	Change expected FIRST(value,2) results to null for out-of-bounds cases Adjust TestRowPatternMatching assertions accordingly	core/trino-main/src/test/java/io/trino/sql/query/TestRowPatternMatching.java

Possibly linked issues

• match_recognize: Logical navigation function FIRST yields unexpected output #26981: The PR restricts the FIRST logical navigation function to the current match in running semantics, fixing the unexpected output reported in the issue where it incorrectly returned out-of-bounds positions.

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