From 45eaca12905c3131bea4e9e2929cb839e5621532 Mon Sep 17 00:00:00 2001
From: Ilya Chernikov <ilya.chernikov@jetbrains.com>
Date: Mon, 23 Jul 2018 16:28:18 +0200
Subject: [PATCH] Add diagnostics chaining

---
 .../script/experimental/api/errorHandling.kt     | 16 ++++++++++++++++
 .../experimental/host/BasicScriptingHost.kt      |  8 ++------
 2 files changed, 18 insertions(+), 6 deletions(-)

diff --git a/libraries/scripting/common/src/kotlin/script/experimental/api/errorHandling.kt b/libraries/scripting/common/src/kotlin/script/experimental/api/errorHandling.kt
index 9345f2eae73..e90363d4d7c 100644
--- a/libraries/scripting/common/src/kotlin/script/experimental/api/errorHandling.kt
+++ b/libraries/scripting/common/src/kotlin/script/experimental/api/errorHandling.kt
@@ -31,11 +31,27 @@ sealed class ResultWithDiagnostics<out R> {
     }
 }
 
+// call chaining
+
+suspend fun <R1, R2> ResultWithDiagnostics<R1>.onSuccess(body: suspend (R1) -> ResultWithDiagnostics<R2>): ResultWithDiagnostics<R2> = when (this) {
+    is ResultWithDiagnostics.Success -> this.reports + body(this.value)
+    is ResultWithDiagnostics.Failure -> this
+}
+
+suspend fun <R> ResultWithDiagnostics<R>.onFailure(body: suspend (ResultWithDiagnostics<R>) -> Unit): ResultWithDiagnostics<R> {
+    if (this is ResultWithDiagnostics.Failure) {
+        body(this)
+    }
+    return this
+}
+
 operator fun <R> List<ScriptDiagnostic>.plus(res: ResultWithDiagnostics<R>): ResultWithDiagnostics<R> = when (res) {
     is ResultWithDiagnostics.Success -> ResultWithDiagnostics.Success(res.value, this + res.reports)
     is ResultWithDiagnostics.Failure -> ResultWithDiagnostics.Failure(this + res.reports)
 }
 
+// results creation
+
 fun <R : Any> R.asSuccess(reports: List<ScriptDiagnostic> = listOf()): ResultWithDiagnostics.Success<R> =
     ResultWithDiagnostics.Success(this, reports)
 
diff --git a/libraries/scripting/common/src/kotlin/script/experimental/host/BasicScriptingHost.kt b/libraries/scripting/common/src/kotlin/script/experimental/host/BasicScriptingHost.kt
index bf2830e806c..1e42dfdceb0 100644
--- a/libraries/scripting/common/src/kotlin/script/experimental/host/BasicScriptingHost.kt
+++ b/libraries/scripting/common/src/kotlin/script/experimental/host/BasicScriptingHost.kt
@@ -35,12 +35,8 @@ abstract class BasicScriptingHost(
         environment: ScriptEvaluationEnvironment
     ): ResultWithDiagnostics<EvaluationResult> =
         runInCoroutineContext {
-            val compiled = compiler(script, scriptDefinition, compileConfiguration)
-            when (compiled) {
-                is ResultWithDiagnostics.Failure -> compiled
-                is ResultWithDiagnostics.Success -> {
-                    evaluator(compiled.value, environment)
-                }
+            compiler(script, scriptDefinition, compileConfiguration).onSuccess {
+                evaluator(it, environment)
             }
         }
 }