fix(adminui): never slice a DB-sourced string with the range operator (#504)

`Scripts.razor` rendered a hash prefix as `@s.SourceHash[..12]…`. `SourceHash` is a plain nvarchar(64) with no length floor, so any value shorter than 12 characters threw ArgumentOutOfRangeException out of BuildRenderTree — unhandled in Blazor, which takes the WHOLE page to an HTTP 500, not just the offending row. Live-reproduced on docker-dev, where two Script rows carry `h1` and `h-abs-hr200`: /scripts was a hard 500. New `Components/Shared/DisplayText.Abbreviate(string?, int)`: - null/blank renders the Admin UI's em-dash placeholder rather than throwing; - a value already within budget renders verbatim with NO ellipsis, so the display never implies text that isn't there (the old markup appended "…" unconditionally, outside the slice — `h1` would have shown as `h1…`); - a maxLength < 1 is clamped, so a display bug cannot become a page crash. Applied to every unguarded range-operator slice over a DB-sourced string found by sweeping the AdminUI for `[..N]`: Scripts.razor SourceHash (the reported crash) Certificates.razor Thumbprint (read off the on-disk store) Deployments.razor x2 RevisionHash Clusters/ClusterOverview.razor RevisionHash The other `[..N]` hits are safe and untouched: Guid.ToString("N") slices (always 32 chars) and the `Length > 60 ? [..60]` ternaries that self-guard. NOTE — the issue text blamed the docker-dev seed; that was wrong and is corrected on #504. `seed-clusters.sql` inserts only ServerCluster, ClusterNode and LdapGroupRoleMapping. The short-hash rows came from earlier live-gate authoring. A freshly seeded rig is fine; the trigger is any Script row that did not go through ScriptEdit / UnsTreeService.HashSource — REST-API authored, hand-inserted, or migrated in. Tests: 14 new in DisplayTextTests, covering the short/null/blank/clamped cases and a never-throws sweep over every value x budget combination. AdminUI suite 739/739. Live-verified on docker-dev (AdminUI has no bUnit): /scripts 500 -> 200 across both central nodes, rendering `hash=h1` and `hash=h-abs-hr200` in full; /deployments still truncates 64-char hashes at 12 with the ellipsis; /certificates and /clusters/MAIN unchanged.
2026-07-26 09:43:48 -04:00
parent 755ae1aa3f
commit 47d148daf9
6 changed files with 145 additions and 5 deletions
@@ -0,0 +1,95 @@
+using Shouldly;
+using Xunit;
+using ZB.MOM.WW.OtOpcUa.AdminUI.Components.Shared;
+
+namespace ZB.MOM.WW.OtOpcUa.AdminUI.Tests;
+
+/// <summary>
+///     #504 — <see cref="DisplayText.Abbreviate"/>, the null/short-safe replacement for the
+///     <c>@value[..N]</c> range-operator slices the Admin UI used to abbreviate hashes and thumbprints.
+/// </summary>
+/// <remarks>
+///     The bug being pinned: a range operator over an unvalidated DB string throws
+///     <see cref="System.ArgumentOutOfRangeException"/> out of <c>BuildRenderTree</c>, which is unhandled
+///     in Blazor and takes the WHOLE page to an HTTP 500 — not just the offending row. Nothing enforces a
+///     minimum length at the schema, entity, or render layer, so the short-input cases below are the ones
+///     that matter; the happy path is almost incidental.
+/// </remarks>
+[Trait("Category", "Unit")]
+public sealed class DisplayTextTests
+{
+    /// <summary>A value longer than the budget is truncated and marked with an ellipsis — the normal
+    /// case for a 64-char SHA-256.</summary>
+    [Fact]
+    public void A_long_value_is_truncated_and_marked()
+    {
+        DisplayText.Abbreviate(new string('a', 64), 12).ShouldBe(new string('a', 12) + "…");
+    }
+
+    /// <summary>The regression: a value SHORTER than the budget must render, not throw. This is exactly
+    /// what a hand-inserted / API-authored <c>SourceHash</c> like <c>h1</c> hits.</summary>
+    [Theory]
+    [InlineData("h1", 12)]
+    [InlineData("h-abs-hr200", 12)] // 11 chars — one short of the old slice, the original crash
+    [InlineData("abc", 16)]
+    [InlineData("x", 64)]
+    public void A_value_shorter_than_the_budget_renders_verbatim(string value, int maxLength)
+    {
+        DisplayText.Abbreviate(value, maxLength).ShouldBe(value);
+    }
+
+    /// <summary>No ellipsis when nothing was dropped — the display must never imply text that is not
+    /// there. (The old markup appended "…" unconditionally, outside the slice.)</summary>
+    [Fact]
+    public void A_short_value_gets_no_ellipsis()
+    {
+        DisplayText.Abbreviate("h1", 12).ShouldNotContain("…");
+    }
+
+    /// <summary>A value exactly at the budget is the boundary — it fits, so it is neither truncated nor
+    /// marked.</summary>
+    [Fact]
+    public void A_value_exactly_at_the_budget_is_untouched()
+    {
+        DisplayText.Abbreviate("123456789012", 12).ShouldBe("123456789012");
+    }
+
+    /// <summary>Null / blank render as the Admin UI's em-dash placeholder rather than throwing or
+    /// producing a stray ellipsis.</summary>
+    [Theory]
+    [InlineData(null)]
+    [InlineData("")]
+    [InlineData("   ")]
+    public void A_null_or_blank_value_renders_the_placeholder(string? value)
+    {
+        DisplayText.Abbreviate(value, 12).ShouldBe(DisplayText.Empty);
+    }
+
+    /// <summary>A nonsensical budget is clamped rather than allowed to throw — a display bug must not
+    /// become a page crash, which is the whole point of this helper.</summary>
+    [Theory]
+    [InlineData(0)]
+    [InlineData(-1)]
+    [InlineData(int.MinValue)]
+    public void A_non_positive_budget_is_clamped_not_thrown(int maxLength)
+    {
+        DisplayText.Abbreviate("abcdef", maxLength).ShouldBe("a…");
+    }
+
+    /// <summary>Whatever the inputs, it never throws — the property that keeps a bad row from killing a
+    /// page. Includes the shapes that broke the old code.</summary>
+    [Fact]
+    public void It_never_throws_for_any_combination()
+    {
+        string?[] values = [null, "", " ", "h1", "h-abs-hr200", new string('f', 64), "…"];
+        int[] budgets = [int.MinValue, -1, 0, 1, 12, 16, 64, int.MaxValue];
+
+        foreach (var value in values)
+        {
+            foreach (var budget in budgets)
+            {
+                Should.NotThrow(() => DisplayText.Abbreviate(value, budget));
+            }
+        }
+    }
+}