From d5aeecd7d3d2c1d69ffcabc0a944bbb1b85ece8a Mon Sep 17 00:00:00 2001
From: Marc Durdin <marc@durdin.net>
Date: Tue, 11 Jul 2023 12:55:19 +0700
Subject: [PATCH] chore(developer): suppress excessive messages in kmc

Fixes #9147.
---
 .../kmc/src/messages/NodeCompilerCallbacks.ts | 31 +++++++++++++++++--
 developer/src/kmc/src/messages/messages.ts    |  3 ++
 2 files changed, 31 insertions(+), 3 deletions(-)

diff --git a/developer/src/kmc/src/messages/NodeCompilerCallbacks.ts b/developer/src/kmc/src/messages/NodeCompilerCallbacks.ts
index 5c1d4c8f75..376ef5b6d9 100644
--- a/developer/src/kmc/src/messages/NodeCompilerCallbacks.ts
+++ b/developer/src/kmc/src/messages/NodeCompilerCallbacks.ts
@@ -9,9 +9,6 @@ import { CompilerCallbacks, CompilerSchema, CompilerEvent,
 import { InfrastructureMessages } from './messages.js';
 import chalk from 'chalk';
 import supportsColor from 'supports-color';
-/**
- * Concrete implementation for CLI use
- */
 
 const color = chalk.default;
 const severityColors: {[value in CompilerErrorSeverity]: chalk.Chalk} = {
@@ -22,10 +19,20 @@ const severityColors: {[value in CompilerErrorSeverity]: chalk.Chalk} = {
   [CompilerErrorSeverity.Fatal]: color.redBright,
 };
 
+/**
+ * Maximum messages that will be emitted before suppressing further messages.
+ * We may in the future make this user configurable?
+ */
+const MaxMessagesDefault = 100;
+
+/**
+ * Concrete implementation for CLI use
+ */
 export class NodeCompilerCallbacks implements CompilerCallbacks {
   /* NodeCompilerCallbacks */
 
   messages: CompilerEvent[] = [];
+  messageCount = 0;
 
   constructor(private options: CompilerCallbackOptions) {
     color.enabled = this.options.color ?? (supportsColor.stdout ? supportsColor.stdout.hasBasic : false);
@@ -33,6 +40,7 @@ export class NodeCompilerCallbacks implements CompilerCallbacks {
 
   clear() {
     this.messages = [];
+    this.messageCount = 0;
   }
 
   /**
@@ -102,6 +110,23 @@ export class NodeCompilerCallbacks implements CompilerCallbacks {
       return;
     }
 
+    // We don't use this.messages.length because we only want to count visible
+    // messages, and there's no point in recalculating the total for every
+    // message emitted.
+    this.messageCount++;
+    if(this.messageCount > MaxMessagesDefault) {
+      return;
+    }
+
+    if(this.messageCount == MaxMessagesDefault) {
+      // We've hit our event limit so we'll suppress further messages, and emit
+      // our little informational message so users know what's going on. Note
+      // that this message will not be included in the this.messages array, and
+      // that will continue to collect all messages; this only affects the
+      // console emission of messages.
+      event = InfrastructureMessages.Info_TooManyMessages({count: MaxMessagesDefault});
+    }
+
     const severityColor = severityColors[CompilerError.severity(event.code)] ?? color.reset;
     const messageColor = this.messageSpecialColor(event) ?? color.reset;
     process.stdout.write(
diff --git a/developer/src/kmc/src/messages/messages.ts b/developer/src/kmc/src/messages/messages.ts
index c2fb3fe025..b2e0a54149 100644
--- a/developer/src/kmc/src/messages/messages.ts
+++ b/developer/src/kmc/src/messages/messages.ts
@@ -61,5 +61,8 @@ export class InfrastructureMessages {
     `Project ${o.filename} failed to build.`)});
   static INFO_ProjectNotBuiltSuccessfully = SevInfo | 0x000C;
 
+  static Info_TooManyMessages = (o:{count:number}) => m(this.INFO_TooManyMessages,
+    `More than ${o.count} warnings or errors received; suppressing further messages.`);
+  static INFO_TooManyMessages = SevInfo | 0x000D;
 }