#13603 Fix silent wrong results when combining aggregating functions with if in calculator expressions

[Copilot]

When using min, max, sum, or avg with a single vector argument inside an if expression, expandIfStatements() was producing silently wrong results — no error, just incorrect data.

Root Cause

expandIfStatements() blindly replaces every vector variable with its indexed form var[i]. This corrupts aggregating calls:

c := if(a > min(b), a, b)

Expanded (buggy):

for (var i := 0; i < min(c[], a[], b[]); i += 1)
{
    c[i] := if(a[i] > min(b[i]), a[i], b[i]);  // min(scalar) = scalar, not global min!
}

In exprtk, min(scalar) returns the scalar unchanged (vararg_min_op::process_1), so the global minimum threshold silently becomes a per-element comparison.

Fix

Before the element-wise replacement loop, detect func(single_var) patterns (min, max, sum, avg) and pre-compute them as scalar var declarations outside the for loop:

var ri_agg_0 := min(b);
for (var i := 0; i < min(c[], a[], b[]); i += 1)
{
    c[i] := if(a[i] > ri_agg_0, a[i], b[i]);
}

Multi-argument calls like min(a, b) are unaffected — only sole-argument aggregations are pre-computed.

Changes

• ThirdParty/expressionparser/ExpressionParserImpl.cpp: Pre-compute aggregating function calls with a single vector argument as scalars before the for loop expansion
• ApplicationLibCode/UnitTests/RicExpressionParser-Test.cpp: Add ExpandIfWithMinAggregation test verifying c := if(a > min(b), a, b) uses the global minimum, not per-element comparison

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