Add 4 more AL/BC testing patterns from Luc van Vugt's fluxxus.nl blog

Fourth batch from CURABIS ApS, mined from an external BC/NAV testing expert's blog archive (fluxxus.nl). Confirm+StrSubstNo interaction with ConfirmHandler, Table Relation Test's OnAfterRemoveTableRelation exclusion hook (verified against BCApps source, codeunit 134926), committing shared lazy-Initialize fixture data, and Assert.IsFalse vs asserterror for boolean checks.

microsoft/knowledge/testing/use-assert-isfalse-not-asserterror-for-boolean-checks.md

@@ -0,0 +1,26 @@
+---
+bc-version: [all]
+domain: testing
+keywords: [assert, isfalse, istrue, asserterror, boolean-check, negative-test]
+technologies: [al]
+countries: [w1]
+application-area: [all]
+---
+
+# Use Assert.IsFalse to check a boolean result, not asserterror around Assert.IsTrue
+
+## Description
+
+`asserterror` exists to assert that a statement raises a runtime error; it is not a general-purpose way to invert a boolean check. Wrapping `asserterror Assert.IsTrue(SomeFunc(), Msg)` to verify that `SomeFunc()` returns `false` tests whether `Assert.IsTrue`'s own error-raising behavior fired, not the value `SomeFunc()` actually returned.
+
+## Best Practice
+
+When the code under test returns a `Boolean` rather than raising an error, assert the value directly with `Assert.IsFalse(SomeFunc(), Msg)` (or `Assert.IsTrue` for the positive case). Reserve `asserterror` for statements expected to actually raise an error.
+
+See sample: `use-assert-isfalse-not-asserterror-for-boolean-checks.good.al`.
+
+## Anti Pattern
+
+`asserterror Assert.IsTrue(SomeFunc(), Msg);` to verify `SomeFunc()` is `false`. It passes today because `Assert.IsTrue` happens to raise an error on failure, but it verifies the assertion helper's error-raising behavior, not the value under test.
+
+See sample: `use-assert-isfalse-not-asserterror-for-boolean-checks.bad.al`.