fancy error printing done

README.md

@@ -98,5 +98,44 @@ val b = arrayOf(1, 2, 3, 4)
 println(a.contents == b.contents) // true
 println(b.contents) // [1, 2, 3, 4]
 ```
+### Code error messages
+````kotlin
+val source = Errors.Source("main.kt", MutMultiLineString.from("""
+    fn main() {
+        return 1 + 0
+    }
+""".trimIndent(), ' '))
+
+val errors = listOf(
+    Errors.Error(
+        "cannot return integer from function with return type void",
+        Errors.Error.Level.ERROR,
+        Errors.Location(source, 1, 11, 5)
+    ),
+    Errors.Error(
+        "return is deprecated. use yeet instead",
+        Errors.Error.Level.WARN,
+        Errors.Location(source, 1, 4, 6)
+    ),
+    Errors.Error(
+        "useless addition",
+        Errors.Error.Level.INFO,
+        Errors.Location(source, 1, 13, 3),
+        isHint = true
+    ),
+    Errors.Error(
+        "Visit https://www.example.com/doc/yeet for more information",
+        Errors.Error.Level.INFO,
+        Errors.Location(source, 1, 0, 0),
+        isLongDesc = true
+    )
+)
+
+val config = Errors.PrintConfig()
+
+Errors.print(config, errors)
+````
+Output:
+![img.png](img.png)
 ### Either
 No example yet

src/main/kotlin/blitz/codeerrors/Errors.kt

@@ -1,5 +1,8 @@
 package blitz.codeerrors
 
+import blitz.collections.inBounds
+import blitz.str.ColoredChar
+import blitz.str.MutMultiColoredMultiLineString
 import blitz.str.MutMultiLineString
 import blitz.str.MutString
 import blitz.term.AnsiiMode
@@ -23,6 +26,7 @@ object Errors {
         val level: Level,
         val loc: Location,
         val isHint: Boolean = false,
+        val isLongDesc: Boolean = false,
     ) {
         enum class Level {
             INFO,
@@ -41,19 +45,19 @@ object Errors {
 
     data class PrintConfig(
         val styles: Map<Error.Level, AnsiiMode> = mapOf(
-            Error.Level.INFO to Terminal.COLORS.WHITE.fg,
+            Error.Level.INFO to Terminal.COLORS.MAGENTA.fg,
             Error.Level.WARN to Terminal.COLORS.YELLOW.fg,
             Error.Level.ERROR to Terminal.COLORS.RED.fg
         ),
         val levelStr: (Error.Level) -> String = {
             when (it) {
-                Error.Level.INFO -> "note"
-                Error.Level.WARN -> "warning"
-                Error.Level.ERROR -> "error"
+                Error.Level.INFO -> "Note"
+                Error.Level.WARN -> "Warning"
+                Error.Level.ERROR -> "Error"
             }
         },
         val underlineString: (len: Int) -> String = {
-            if (it == 0) "" else "^" + "~".repeat(it - 1)
+            if (it == 0) "" else "^" + "^".repeat(it - 1)
         },
     )
 
@@ -63,40 +67,90 @@ object Errors {
             val worst = errors
                 .map { it.level }
                 .reduce { acc, level -> acc + level }
-            Terminal.errln("File: \"${source.file}\"", config.styles[worst]!!)
-            Terminal.errln("================================================================================", config.styles[worst]!!)
+            Terminal.errln("File: \"${source.file}\"", config.styles[worst]!! + Terminal.STYLES.BOLD)
+            Terminal.errln("================================================================================", config.styles[worst]!! + Terminal.STYLES.BOLD)
 
-            val perLines = errors
+            val perLinesMap = errors
                 .groupBy { it.loc.line }
+
+            val perLines = perLinesMap
                 .entries
                 .sortedBy { it.key }
 
-            perLines.forEach { (line, errors) ->
-                errors.asSequence().filterNot { it.isHint }.forEach { err ->
+            perLines.forEachIndexed { index, (line, errors) ->
+                if (index > 0)
+                    Terminal.errln("")
+
+                errors.asSequence().filterNot { it.isHint || it.isLongDesc }.forEach { err ->
                     Terminal.err(config.levelStr(err.level), config.styles[err.level]!!, Terminal.STYLES.BOLD)
-                    Terminal.errln(": ${err.message}", Terminal.STYLES.BOLD)
+                    Terminal.errln(": ${err.message}", Terminal.COLORS.WHITE.brighter.fg, Terminal.STYLES.BOLD)
                 }
 
-                val msg = MutMultiLineString(' ')
-                val lineStr = line.toString()
-                msg[1, 2] = lineStr
-                var nextCol = 3 + lineStr.length
-                msg[0, nextCol] = '|' // TODO: print above and below source but dimmed?
-                msg[1, nextCol] = '|'
-                msg[2, nextCol] = '|'
+                val printPrev = line > 0 && !perLinesMap.containsKey(line - 1)
+                val printNext = source.content.lines.inBounds(line + 1) && !perLinesMap.containsKey(line + 1)
+
+                val worstLine = config.styles[
+                    errors
+                        .map { it.level }
+                        .reduce { acc, level -> acc + level }
+                ]!!
+
+                val msg = MutMultiColoredMultiLineString(fill = ColoredChar(' '))
+
+                val lineStr = (line + 1).toString()
+                msg.set(1, 2, lineStr, worstLine)
+
+                var nextCol = if (printNext) {
+                    val nextLineStr = (line + 2).toString()
+                    msg.set(2, 2, nextLineStr, Terminal.COLORS.WHITE.fg)
+                    3 + nextLineStr.length
+                } else {
+                    3 + lineStr.length
+                }
+
+                if (printPrev)
+                    msg.set(0, 2, line.toString(), Terminal.COLORS.WHITE.fg)
+
+                fun pipe(row: Int, col: Int) =
+                    msg.set(row, col, '|', Terminal.COLORS.WHITE.fg + Terminal.STYLES.BOLD)
+
+                pipe(0, nextCol)
+                msg.set(1, nextCol, '|', worstLine + Terminal.STYLES.BOLD)
+                pipe(2, nextCol)
+
                 nextCol += 2
-                if (line > 0)
-                    msg[0, nextCol] = source.content[line - 1]
-                msg[1, nextCol] = source.content[line]
+                if (printPrev)
+                    msg.set(0, nextCol, source.content[line - 1].toString(), Terminal.COLORS.WHITE.fg)
+                msg.set(1, nextCol, source.content[line].toString(), Terminal.COLORS.WHITE.brighter.fg)
+                if (printNext)
+                    msg.set(2, nextCol, source.content[line + 1].toString(), Terminal.COLORS.WHITE.fg)
 
-                // TODO: underline
+                val byCol = errors.asSequence().sortedBy { it.loc.col }
+                byCol.filterNot { it.isHint || it.isLongDesc }.forEach {
+                    msg.set(2, it.loc.col + nextCol, config.underlineString(it.loc.size), config.styles[it.level]!! + Terminal.STYLES.BOLD)
+                }
 
-                // TODO: hints
+                var row = 3
+                byCol.filter { it.isHint }.forEach {
+                    msg.set(row, it.loc.col + nextCol, config.underlineString(it.loc.size), config.styles[it.level]!! + Terminal.STYLES.BOLD)
+                    val end = it.loc.col + nextCol + it.loc.size
+                    msg.set(row, end + 1, it.message, config.styles[it.level]!!)
+                    pipe(row, nextCol - 2)
+                    row ++
+                }
+
+                row ++
+
+                byCol.filter { it.isLongDesc }.forEach {
+                    val msgLines = MutMultiLineString.from(it.message, fill = ' ')
+                    msg.set(row, nextCol, msgLines, Terminal.COLORS.WHITE.brighter.fg)
+                    row ++
+                }
 
                 Terminal.errln(msg.toString())
             }
 
-            Terminal.errln("================================================================================", config.styles[worst]!!)
+            Terminal.errln("================================================================================", config.styles[worst]!! + Terminal.STYLES.BOLD)
         }
     }
 }
@@ -104,15 +158,32 @@ object Errors {
 fun main() {
     val source = Errors.Source("main.kt", MutMultiLineString.from("""
         fn main() {
-            return 1
+            return 1 + 0
         }
     """.trimIndent(), ' '))
 
     val errors = listOf(
         Errors.Error(
-            "Cannot return integer from function with return type void",
+            "cannot return integer from function with return type void",
             Errors.Error.Level.ERROR,
-            Errors.Location(source, 1, 11, 1)
+            Errors.Location(source, 1, 11, 5)
+        ),
+        Errors.Error(
+            "return is deprecated. use yeet instead",
+            Errors.Error.Level.WARN,
+            Errors.Location(source, 1, 4, 6)
+        ),
+        Errors.Error(
+            "useless addition",
+            Errors.Error.Level.INFO,
+            Errors.Location(source, 1, 13, 3),
+            isHint = true
+        ),
+        Errors.Error(
+            "Visit https://www.example.com/doc/yeet for more information",
+            Errors.Error.Level.INFO,
+            Errors.Location(source, 1, 0, 0),
+            isLongDesc = true
         )
     )
 

src/main/kotlin/blitz/collections/Bounds.kt

@@ -0,0 +1,17 @@
+package blitz.collections
+
+fun <T> List<T>.inBounds(index: Int): Boolean {
+    if (index >= size)
+        return false
+    if (index < 0)
+        return false
+    return true
+}
+
+fun <T> Vec<T>.inBounds(index: Int): Boolean {
+    if (index >= size)
+        return false
+    if (index < 0)
+        return false
+    return true
+}

src/main/kotlin/blitz/collections/MergeNeighbors.kt

@@ -0,0 +1,22 @@
+package blitz.collections
+
+fun <T, G> Iterable<T>.mergeNeighbors(
+    to: MutableList<Pair<G, MutableList<T>>> = mutableListOf(),
+    by: (T) -> G
+): MutableList<Pair<G, MutableList<T>>> {
+    val out = mutableListOf<Pair<G, MutableList<T>>>()
+    forEach {
+        val b = by(it)
+        if (b == out.lastOrNull()?.first)
+            out.last().second.add(it)
+        else
+            out.add(b to mutableListOf(it))
+    }
+    return out
+}
+
+fun <T, G> Sequence<T>.mergeNeighbors(
+    to: MutableList<Pair<G, MutableList<T>>> = mutableListOf(),
+    by: (T) -> G
+): MutableList<Pair<G, MutableList<T>>> =
+    asIterable().mergeNeighbors(to, by)

src/main/kotlin/blitz/str/ColoredChar.kt

@@ -0,0 +1,21 @@
+package blitz.str
+
+import blitz.term.AnsiiMode
+import blitz.term.Terminal
+
+class ColoredChar(
+    val char: Char,
+    val style: AnsiiMode = AnsiiMode(mutableListOf())
+) {
+    override fun equals(other: Any?): Boolean =
+        char == other
+
+    override fun hashCode(): Int =
+        char.hashCode()
+
+    override fun toString(): String =
+        Terminal.encodeString("$char", style)
+}
+
+fun Iterable<ColoredChar>.convToString(): String =
+    joinToString(separator = "")

src/main/kotlin/blitz/str/MutMultiColoredMultiLineString.kt

@@ -0,0 +1,109 @@
+package blitz.str
+
+import blitz.term.AnsiiMode
+
+class MutMultiColoredMultiLineString(
+     var fill: ColoredChar
+) {
+    val lines = mutableListOf<MutMultiColoredString>()
+
+    // TODO: wrap at \n
+
+    override fun equals(other: Any?): Boolean =
+        lines == other
+
+    override fun hashCode(): Int =
+        lines.hashCode()
+
+    /** if out of bounds, extends with @see fill */
+    operator fun get(row: Int, col: Int): ColoredChar {
+        if (row >= lines.size) {
+            repeat(row - lines.size + 1) {
+                lines.add(MutMultiColoredString(fill = fill))
+            }
+        }
+        return lines[row][col]
+    }
+
+    /** if out of bounds, extends with @see fill */
+    operator fun get(row: Int): MutMultiColoredString {
+        if (row >= lines.size) {
+            repeat(row - lines.size + 1) {
+                lines.add(MutMultiColoredString(fill = fill))
+            }
+        }
+        return lines[row]
+    }
+
+    /** if out of bounds, extends with @see fill */
+    operator fun set(row: Int, col: Int, value: ColoredChar) {
+        if (row >= lines.size) {
+            repeat(row - lines.size + 1) {
+                lines.add(MutMultiColoredString(fill = fill))
+            }
+        } else {
+            lines[row].fill = fill
+        }
+        lines[row][col] = value
+    }
+
+    /** if out of bounds, extends with @see fill */
+    operator fun set(row: Int, col: Int, value: Char) =
+        set(row, col, ColoredChar(value))
+
+    /** if out of bounds, extends with @see fill */
+    operator fun set(row: Int, colStart: Int, value: CharSequence) {
+        if (row >= lines.size) {
+            repeat(row - lines.size + 1) {
+                lines.add(MutMultiColoredString(fill = fill))
+            }
+        } else {
+            lines[row].fill = fill
+        }
+        lines[row][colStart] = value
+    }
+
+    /** if out of bounds, extends with @see fill */
+    operator fun set(row: Int, colStart: Int, value: MutMultiColoredString) {
+        if (row >= lines.size) {
+            repeat(row - lines.size + 1) {
+                lines.add(MutMultiColoredString(fill = fill))
+            }
+        } else {
+            lines[row].fill = fill
+        }
+        lines[row][colStart] = value
+    }
+
+    /** if out of bounds, extends with @see fill */
+    fun set(row: Int, colStart: Int, va: Char, style: AnsiiMode) =
+        set(row, colStart, ColoredChar(va, style))
+
+    /** if out of bounds, extends with @see fill */
+    fun set(row: Int, colStart: Int, va: String, style: AnsiiMode) =
+        set(row, colStart, MutMultiColoredString.from(va, style))
+
+    /** if out of bounds, extends with @see fill */
+    operator fun set(rowStart: Int, colStart: Int, value: MutMultiLineString) {
+        value.lines.forEachIndexed { index, line ->
+            this[index + rowStart, colStart] = line
+        }
+    }
+
+    /** if out of bounds, extends with @see fill */
+    operator fun set(rowStart: Int, colStart: Int, value: MutMultiLineString, style: AnsiiMode) {
+        value.lines.forEachIndexed { index, line ->
+            this.set(index + rowStart, colStart, line.toString(), style)
+        }
+    }
+
+    /** if out of bounds, extends with @see fill */
+    operator fun set(rowStart: Int, colStart: Int, value: MutMultiColoredMultiLineString) {
+        value.lines.forEachIndexed { index, line ->
+            this[index + rowStart, colStart] = line
+        }
+    }
+
+    override fun toString(): String =
+        lines.joinToString(separator = "\n")
+}

src/main/kotlin/blitz/str/MutMultiColoredString.kt

@@ -0,0 +1,92 @@
+package blitz.str
+
+import blitz.collections.mergeNeighbors
+import blitz.term.AnsiiMode
+import blitz.term.Terminal
+
+class MutMultiColoredString(var fill: ColoredChar) {
+    val chars = mutableListOf<ColoredChar>()
+
+    val length
+        get() = chars.size
+
+    override fun equals(other: Any?): Boolean =
+        chars == other
+
+    override fun hashCode(): Int =
+        chars.hashCode()
+
+    override fun toString(): String {
+        val byColors = chars.mergeNeighbors { it.style }
+        val res = MutString(fill = ' ')
+        byColors.forEach {
+            val style = it.first
+            val str = it.second.convToString()
+            res.append(Terminal.encodeString(str, style))
+        }
+        return res.toString()
+    }
+
+    fun add(str: String, style: AnsiiMode = AnsiiMode(mutableListOf())) {
+        str.mapTo(chars) { ColoredChar(it, style) }
+    }
+
+    fun add(str: Iterable<ColoredChar>) {
+        chars.addAll(str)
+    }
+
+    fun add(ch: ColoredChar) {
+        chars.add(ch)
+    }
+
+    operator fun get(index: Int): ColoredChar {
+        if (index >= length) {
+            repeat(index - length + 1) {
+                chars.add(fill)
+            }
+        }
+        return chars[index]
+    }
+
+    operator fun set(index: Int, value: ColoredChar) {
+        if (index >= length) {
+            repeat(index - length + 1) {
+                chars.add(fill)
+            }
+        }
+        chars[index] = value
+    }
+
+    fun set(start: Int, str: CharSequence, style: AnsiiMode) {
+        if (start + str.length >= length) {
+            repeat(start + str.length - length + 1) {
+                chars.add(fill)
+            }
+        }
+        str.forEachIndexed { index, c ->
+            chars[start + index] = ColoredChar(c, style)
+        }
+    }
+
+    operator fun set(start: Int, str: CharSequence) {
+        set(start, str, AnsiiMode(mutableListOf()))
+    }
+
+    operator fun set(start: Int, str: MutMultiColoredString) {
+        if (start + str.length >= length) {
+            repeat(start + str.length - length + 1) {
+                chars.add(fill)
+            }
+        }
+        str.chars.forEachIndexed { index, c ->
+            chars[start + index] = c
+        }
+    }
+
+    companion object {
+        fun from(str: String, style: AnsiiMode = AnsiiMode(mutableListOf())) =
+            MutMultiColoredString(fill = ColoredChar(' ')).also {
+                it.add(str, style)
+            }
+    }
+}

src/main/kotlin/blitz/str/MutMultiLineString.kt

@@ -7,6 +7,12 @@ class MutMultiLineString(
 
     // TODO: wrap at \n
 
+    override fun equals(other: Any?): Boolean =
+        lines == other
+
+    override fun hashCode(): Int =
+        lines.hashCode()
+
     /** if out of bounds, extends with @see fill */
     operator fun get(row: Int, col: Int): Char {
         if (row >= lines.size) {

src/main/kotlin/blitz/str/MutString.kt

@@ -1,11 +1,19 @@
 package blitz.str
 
+import java.util.stream.IntStream
+
 class MutString(
     init: String = "",
     var fill: Char
 ): CharSequence, Appendable {
     private val builder = StringBuilder(init)
 
+    override fun chars(): IntStream =
+        builder.chars()
+
+    override fun codePoints(): IntStream =
+        builder.codePoints()
+
     override val length: Int
         get() = builder.length
 
@@ -30,12 +38,12 @@ class MutString(
 
     /** if out of bounds, extends with @see fill */
     operator fun set(start: Int, str: CharSequence) {
-        if (start >= length) {
-            repeat(start - length + 1) {
+        if (start + str.length >= length) {
+            repeat(start + str.length - length + 1) {
                 builder.append(fill)
             }
         }
-        builder.insert(start, str)
+        builder.replace(start, start + str.length, str.toString())
     }
 
     override fun toString(): String =

src/main/kotlin/blitz/term/AnsiiStr.kt

@@ -5,11 +5,17 @@ class AnsiiMode(internal val values: MutableList<Int>) {
 
     operator fun plus(other: AnsiiMode): AnsiiMode =
         AnsiiMode((values + other.values).toMutableList())
+
+    override fun equals(other: Any?): Boolean =
+        values == other
+
+    override fun hashCode(): Int =
+        values.hashCode()
 }
 
 private val escape = (27).toChar()
 
-fun ansiiStr(str: String, vararg modes: AnsiiMode) =
+internal fun ansiiStr(str: String, vararg modes: AnsiiMode) =
     if (modes.isEmpty())
         str
     else

src/main/kotlin/blitz/term/Terminal.kt

@@ -38,6 +38,23 @@ object Terminal {
         val darker by lazy { Color(AnsiiMode(darkerChannel(ch(fg))), AnsiiMode(darkerChannel(ch(bg)))) }
     }
 
+    /** Escape-sequence safe string length */
+    fun len(str: String): Int {
+        var len = 0
+        var ansii = false
+        str.forEach {
+            if (ansii) {
+                if (it == 'm')
+                    ansii = false
+            } else if (it.code == 27) {
+                ansii = true
+            } else {
+                len ++
+            }
+        }
+        return len
+    }
+
     fun encodeString(str: String, vararg modes: AnsiiMode) =
         ansiiStr(str, *modes)