terminal: simplify scraping output (IJ-CR-121332)

GitOrigin-RevId: 927d3066c83eb475695e9614808dadb05988d134

plugins/terminal/src/org/jetbrains/plugins/terminal/exp/ShellCommandOutputScraper.kt

@@ -52,7 +52,7 @@ internal class ShellCommandOutputScraper(private val session: TerminalSession,
 
   fun scrapeOutput(): StyledCommandOutput {
     session.model.withContentLock {
-      val outputBuilder = OutputBuilder(textBuffer.width)
+      val outputBuilder = OutputBuilder()
       if (!textBuffer.isUsingAlternateBuffer) {
         outputBuilder.addLines(textBuffer.historyBuffer)
       }
@@ -62,11 +62,10 @@ internal class ShellCommandOutputScraper(private val session: TerminalSession,
   }
 }
 
-private class OutputBuilder(private val columns: Int) {
+private class OutputBuilder {
   private val output: StringBuilder = StringBuilder()
   private val styles: MutableList<StyleRange> = mutableListOf()
   private var pendingNewLines: Int = 0
-  private var pendingNuls: Int = 0
 
   fun addLines(linesBuffer: LinesBuffer) {
     for (i in 0 until linesBuffer.lineCount) {
@@ -75,26 +74,13 @@ private class OutputBuilder(private val columns: Int) {
   }
 
   private fun addLine(line: TerminalLine) {
-    var addedLength = 0
     line.forEachEntry { entry ->
-      val charBuffer: CharBuffer = entry.text
-      val length = charBuffer.length
-      addedLength += length
-      if (length > 0) {
-        if (entry.isNul) {
-          pendingNuls += length
-        }
-        else {
-          addTextChunk(charBuffer.normalize(), entry.style)
-        }
+      if (entry.text.isNotEmpty() && !entry.isNul) {
+        addTextChunk(entry.text.normalize(), entry.style)
       }
     }
-    if (line.isWrapped) {
-      pendingNuls += (columns - addedLength).coerceAtLeast(0)
-    }
-    else {
+    if (!line.isWrapped) {
       pendingNewLines++
-      pendingNuls = 0
     }
   }
 
@@ -109,10 +95,6 @@ private class OutputBuilder(private val columns: Int) {
         output.append("\n")
       }
       pendingNewLines = 0
-      repeat(pendingNuls) {
-        output.append(' ')
-      }
-      pendingNuls = 0
       val startOffset = output.length
       output.append(text)
       if (style != TextStyle.EMPTY) {

plugins/terminal/tests/org/jetbrains/plugins/terminal/block/BlockTerminalTest.kt

@@ -11,6 +11,7 @@ import com.intellij.testFramework.ProjectRule
 import com.intellij.testFramework.RuleChain
 import com.jediterm.core.util.TermSize
 import kotlinx.coroutines.*
+import org.jetbrains.plugins.terminal.block.testApps.MoveCursorToLineEndAndPrint
 import org.jetbrains.plugins.terminal.block.testApps.SimpleTextRepeater
 import org.jetbrains.plugins.terminal.exp.*
 import org.jetbrains.plugins.terminal.exp.completion.IJShellRuntimeDataProvider
@@ -118,6 +119,39 @@ class BlockTerminalTest(private val shellPath: String) {
     assertCommandResult(0, SimpleTextRepeater.Helper.getExpectedOutput(items), outputFuture)
   }
 
+  @Test
+  fun `mix of empty area and text #1`() {
+    val termSize = TermSize(10, 10)
+    val session = startBlockTerminalSession(termSize)
+    val outputFuture: CompletableFuture<CommandResult> = getCommandResultFuture(session)
+    val textsToPrint = listOf("foo")
+    session.sendCommandToExecuteWithoutAddingToHistory(MoveCursorToLineEndAndPrint.Helper.generateCommandLine(textsToPrint))
+    assertCommandResult(0, MoveCursorToLineEndAndPrint.Helper.getExpectedOutput(termSize, textsToPrint), outputFuture)
+  }
+
+  @Test
+  fun `mix of empty area and text #2`() {
+    val termSize = TermSize(10, 10)
+    val session = startBlockTerminalSession(termSize)
+    val outputFuture: CompletableFuture<CommandResult> = getCommandResultFuture(session)
+    val textsToPrint = listOf("foo", "a".repeat(termSize.columns  + 1), "b")
+    session.sendCommandToExecuteWithoutAddingToHistory(MoveCursorToLineEndAndPrint.Helper.generateCommandLine(textsToPrint))
+    assertCommandResult(0, MoveCursorToLineEndAndPrint.Helper.getExpectedOutput(termSize, textsToPrint), outputFuture)
+  }
+
+  @Test
+  fun `mix of empty area and text #3`() {
+    val termSize = TermSize(15, 15)
+    val session = startBlockTerminalSession(termSize)
+    val outputFuture: CompletableFuture<CommandResult> = getCommandResultFuture(session)
+    val textsToPrint = ('a'..'z').map {
+      val cnt = it - 'a'
+      it.toString().repeat(cnt) + cnt.toString()
+    }
+    session.sendCommandToExecuteWithoutAddingToHistory(MoveCursorToLineEndAndPrint.Helper.generateCommandLine(textsToPrint))
+    assertCommandResult(0, MoveCursorToLineEndAndPrint.Helper.getExpectedOutput(termSize, textsToPrint), outputFuture)
+  }
+
   private fun createCommandSentDeferred(session: TerminalSession): CompletableDeferred<Unit> {
     val generatorCommandSent = CompletableDeferred<Unit>()
     val generatorCommandSentDisposable = Disposer.newDisposable().also { disposable ->

plugins/terminal/tests/org/jetbrains/plugins/terminal/block/testApps/MoveCursorToLineEndAndPrint.kt

@@ -0,0 +1,41 @@
+// Copyright 2000-2023 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
+package org.jetbrains.plugins.terminal.block.testApps
+
+import com.jediterm.core.util.TermSize
+import org.jetbrains.plugins.terminal.exp.util.TerminalSessionTestUtil
+
+object MoveCursorToLineEndAndPrint {
+
+  @JvmStatic
+  fun main(arg: Array<String>) {
+    check(arg.isNotEmpty()) { "One or more arguments are expected, got " + arg.size }
+    for (textToPrint in arg) {
+      check(textToPrint.isNotEmpty())
+      // [java.io.Console] doesn't provide terminal width =>
+      // To place the cursor at the line end, move the cursor far away to the right - it should stop as it reaches the edge.
+      val infiniteWidth = 10000
+      print("\u001b[${infiniteWidth}C")
+      print(textToPrint)
+    }
+    println() // new line to get rid of trailing '%' in zsh
+  }
+
+  object Helper {
+    fun generateCommandLine(textsToPrint: List<String>): String {
+      return TerminalSessionTestUtil.getJavaShellCommand(MoveCursorToLineEndAndPrint::class.java, *textsToPrint.toTypedArray())
+    }
+
+    fun getExpectedOutput(termSize: TermSize, textsToPrint: List<String>): String {
+      return " ".repeat(termSize.columns - 1) + textsToPrint.dropLast(1).joinToString("") {
+        val emptyColumns = termSize.columns - (it.length - 1) % termSize.columns
+        check(emptyColumns > 0)
+        if (emptyColumns == termSize.columns) {
+          it.dropLast(1) // string ends at the right edge
+        }
+        else {
+          it + " ".repeat(emptyColumns - 1)
+        }
+      } + textsToPrint.last() + System.lineSeparator()
+    }
+  }
+}