FIR IDE: introduce KtType rendering

2020-08-06 16:27:27 +03:00
parent 9f33d0147c
commit 36a161080f
2 changed files with 217 additions and 0 deletions
@@ -0,0 +1,111 @@
+/*
+ * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.idea.frontend.api.types
+
+import org.jetbrains.kotlin.idea.frontend.api.*
+import org.jetbrains.kotlin.name.ClassId
+
+object KtTypeRenderer {
+    fun render(type: KtType, options: KtTypeRendererOptions = KtTypeRendererOptions.DEFAULT): String = type.withValidityAssertion {
+        buildString { render(type, options) }
+    }
+
+    private fun StringBuilder.render(type: KtType, options: KtTypeRendererOptions) {
+        when (type) {
+            is KtDenotableType -> when (type) {
+                is KtClassType -> {
+                    render(type.classId, options)
+                    renderTypeArgumentsIfNotEmpty(type.typeArguments, options)
+                    renderNullability(type.nullability)
+                }
+                is KtTypeParameterType -> {
+                    append(type.name.asString())
+                    renderNullability(type.nullability)
+                }
+            }
+            is KtNonDenotableType -> when (type) {
+                is KtFlexibleType -> inParens {
+                    render(type.lowerBound, options)
+                    append("..")
+                    render(type.upperBound, options)
+                }
+                is KtIntersectionType -> inParens {
+                    type.conjuncts.forEachIndexed { index, conjunct ->
+                        render(conjunct, options)
+                        if (index != type.conjuncts.lastIndex) {
+                            append("&")
+                        }
+                    }
+                }
+            }
+            is KtErrorType -> {
+                append(type.error)
+            }
+            else -> error("Unsupported type ${type::class}")
+        }
+    }
+
+    private fun StringBuilder.renderTypeArgumentsIfNotEmpty(typeArguments: List<KtTypeArgument>, options: KtTypeRendererOptions) {
+        if (typeArguments.isNotEmpty()) {
+            append("<")
+            typeArguments.forEachIndexed { index, typeArgument ->
+                render(typeArgument, options)
+                if (index != typeArguments.lastIndex) {
+                    append(", ")
+                }
+            }
+            append(">")
+        }
+    }
+
+    private fun StringBuilder.render(typeArgument: KtTypeArgument, options: KtTypeRendererOptions) {
+        when (typeArgument) {
+            KtStarProjectionTypeArgument -> {
+                append("*")
+            }
+            is KtTypeArgumentWithVariance -> {
+                val varianceWithSpace = when (typeArgument.variance) {
+                    KtTypeArgumentVariance.COVARIANT -> "out "
+                    KtTypeArgumentVariance.CONTRAVARIANT -> "in "
+                    KtTypeArgumentVariance.INVARIANT -> ""
+                }
+                append(varianceWithSpace)
+                render(typeArgument.type, options)
+            }
+        }
+    }
+
+    private fun StringBuilder.renderNullability(nullability: KtTypeNullability) {
+        if (nullability == KtTypeNullability.NULLABLE) {
+            append("?")
+        }
+    }
+
+    private fun StringBuilder.render(classId: ClassId, options: KtTypeRendererOptions) {
+        if (options.renderFqNames) {
+            append(classId.asString().replace('/', '.'))
+        } else {
+            append(classId.shortClassName.asString())
+        }
+    }
+
+    private inline fun StringBuilder.inParens(render: StringBuilder.() -> Unit) {
+        append("(")
+        render()
+        append(")")
+
+    }
+}
+
+data class KtTypeRendererOptions(
+    val renderFqNames: Boolean,
+) {
+    companion object {
+        val DEFAULT = KtTypeRendererOptions(
+            renderFqNames = true
+        )
+    }
+}