test(compose): instrumented coverage for MentionPreservingInputTransformation

11 cases driving the predicate matrix against a real TextFieldState on device: - mention-free text passes through - pure delete fully covering a mention is allowed - partial overlap (at start, at end, inside) collapses atomically - scope-exact replace with non-empty text collapses (SwiftKey case) - scope-broader replace passes through - append after mention preserves it - trailing space and trailing newline are consumed during atomic collapse - multiple mentions: only the touched one collapses - cheap-gate path (mention-free original) is verified All 11 pass on Pixel 9a; gives the predicate a regression net so future predicate-tuning doesn't reintroduce the @Vitor Pamplona bug. Run via: ./gradlew :amethyst:connectedPlayDebugAndroidTest \ -Pandroid.testInstrumentationRunnerArguments.class=\ com.vitorpamplona.amethyst.MentionPreservingInputTransformationTest Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-04-27 10:51:53 +02:00
parent 338080115f
commit c78c133675
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+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+@file:OptIn(ExperimentalFoundationApi::class)
+
+package com.vitorpamplona.amethyst
+
+import androidx.compose.foundation.ExperimentalFoundationApi
+import androidx.compose.foundation.text.input.TextFieldBuffer
+import androidx.compose.foundation.text.input.TextFieldState
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import com.vitorpamplona.amethyst.ui.actions.MentionPreservingInputTransformation
+import org.junit.Assert.assertEquals
+import org.junit.Test
+import org.junit.runner.RunWith
+
+/**
+ * Drives [MentionPreservingInputTransformation] against a real [TextFieldState]
+ * with simulated IME edits. The npub literal has no metadata loaded — these
+ * tests only exercise the input-side guard, which keys off the underlying bech32
+ * text rather than any display-name resolution.
+ */
+@RunWith(AndroidJUnit4::class)
+class MentionPreservingInputTransformationTest {
+    /** 64 characters: leading `@` + bech32 (`npub1` + 58 chars). */
+    private val npub = "@npub1gcxzte5zlkncx26j68ez60fzkvtkm9e0vrwdcvsjakxf9mu9qewqlfnj5z"
+
+    /**
+     * Apply [stage] inside an edit session, then run the InputTransformation
+     * exactly as the framework would, and return the committed text.
+     */
+    private fun TextFieldState.applyChange(stage: TextFieldBuffer.() -> Unit): String {
+        edit {
+            stage()
+            with(MentionPreservingInputTransformation) {
+                transformInput()
+            }
+        }
+        return text.toString()
+    }
+
+    @Test
+    fun mentionFreeText_passesThrough() {
+        val state = TextFieldState("hello world")
+        val result = state.applyChange { replace(0, 5, "HELLO") }
+        assertEquals("HELLO world", result)
+    }
+
+    @Test
+    fun pureDeleteFullyCoveringMention_passesThrough() {
+        val state = TextFieldState(npub)
+        val result = state.applyChange { replace(0, npub.length, "") }
+        assertEquals("", result)
+    }
+
+    @Test
+    fun partialDeleteInsideMention_collapsesAtomically() {
+        val state = TextFieldState(npub)
+        // delete a chunk near the end of the bech32
+        val result = state.applyChange { replace(60, npub.length, "") }
+        assertEquals("", result)
+    }
+
+    @Test
+    fun partialDeleteAtMentionStart_collapsesAtomically() {
+        val state = TextFieldState(npub)
+        // delete the leading "@npub" prefix only
+        val result = state.applyChange { replace(0, 5, "") }
+        assertEquals("", result)
+    }
+
+    @Test
+    fun scopeExactReplaceWithNonEmpty_collapsesAtomically() {
+        // SwiftKey case: IME fully covers the mention range and writes a
+        // shortened replacement (e.g. one of the multi-word display tokens).
+        val state = TextFieldState(npub)
+        val result = state.applyChange { replace(0, npub.length, "@John") }
+        assertEquals("", result)
+    }
+
+    @Test
+    fun scopeBroaderReplace_passesThrough() {
+        // Select-all + type: change covers the mention plus surrounding text.
+        // Treated as a deliberate broader edit; the typed character is preserved.
+        val state = TextFieldState("hi $npub world")
+        val result = state.applyChange { replace(0, length, "x") }
+        assertEquals("x", result)
+    }
+
+    @Test
+    fun appendAfterMention_passesThrough() {
+        val state = TextFieldState(npub)
+        val result = state.applyChange { append(" hello") }
+        assertEquals("$npub hello", result)
+    }
+
+    @Test
+    fun mentionWithTrailingSpace_collapseConsumesSpace() {
+        val state = TextFieldState("$npub hello")
+        val result = state.applyChange { replace(60, npub.length, "") }
+        assertEquals("hello", result)
+    }
+
+    @Test
+    fun mentionWithTrailingNewline_collapseConsumesNewline() {
+        val state = TextFieldState("$npub\nhello")
+        val result = state.applyChange { replace(60, npub.length, "") }
+        assertEquals("hello", result)
+    }
+
+    @Test
+    fun multipleMentions_partialOnSecond_onlySecondCollapsed() {
+        val text = "$npub and $npub"
+        val state = TextFieldState(text)
+        // partial delete inside the second mention only
+        val result = state.applyChange { replace(text.length - 4, text.length, "") }
+        assertEquals("$npub and ", result)
+    }
+
+    @Test
+    fun mentionFreeChange_skipsRegexEntirely() {
+        // No "npub1" or "nprofile1" substring in the original text — the
+        // cheap-gate path should exit before any regex work.
+        val state = TextFieldState("hello world this is plain text")
+        val result = state.applyChange { replace(5, 11, "") }
+        assertEquals("hello this is plain text", result)
+    }
+}