From 3dfa874f975dcb6843d8d97187a0ce6adadc2183 Mon Sep 17 00:00:00 2001
From: Luca Elin Haneklau <lhanekla@hellmann.com>
Date: Mon, 2 May 2022 16:36:01 +0200
Subject: [PATCH] Add lit-analyzer cli json-formatter

---
 .../src/lib/cli/analyze-command.ts            |  3 ++
 packages/lit-analyzer/src/lib/cli/cli.ts      |  1 +
 .../src/lib/cli/format/json-formatter.ts      | 49 +++++++++++++++++++
 .../src/lib/cli/lit-analyzer-cli-config.ts    |  2 +-
 4 files changed, 54 insertions(+), 1 deletion(-)
 create mode 100644 packages/lit-analyzer/src/lib/cli/format/json-formatter.ts

diff --git a/packages/lit-analyzer/src/lib/cli/analyze-command.ts b/packages/lit-analyzer/src/lib/cli/analyze-command.ts
index 2c84f962..727533a8 100644
--- a/packages/lit-analyzer/src/lib/cli/analyze-command.ts
+++ b/packages/lit-analyzer/src/lib/cli/analyze-command.ts
@@ -10,6 +10,7 @@ import { CodeDiagnosticFormatter } from "./format/code-diagnostic-formatter.js";
 import { AnalysisStats, DiagnosticFormatter } from "./format/diagnostic-formatter.js";
 import { ListDiagnosticFormatter } from "./format/list-diagnostic-formatter.js";
 import { MarkdownDiagnosticFormatter } from "./format/markdown-formatter.js";
+import { JsonDiagnosticFormatter } from "./format/json-formatter.js";
 import { FormatterFormat, LitAnalyzerCliConfig } from "./lit-analyzer-cli-config.js";
 
 function printText(text: string, config: LitAnalyzerCliConfig) {
@@ -153,6 +154,8 @@ function getFormatter(format: FormatterFormat): DiagnosticFormatter {
 			return new CodeDiagnosticFormatter();
 		case "markdown":
 			return new MarkdownDiagnosticFormatter();
+		case "json":
+			return new JsonDiagnosticFormatter();
 		default:
 			throw new Error(`Unknown format: '${format}'`);
 	}
diff --git a/packages/lit-analyzer/src/lib/cli/cli.ts b/packages/lit-analyzer/src/lib/cli/cli.ts
index fbdfe0c7..b08bc722 100644
--- a/packages/lit-analyzer/src/lib/cli/cli.ts
+++ b/packages/lit-analyzer/src/lib/cli/cli.ts
@@ -51,6 +51,7 @@ export async function cli(): Promise<void> {
                             o code                Highlight problems in the code (default)
                             o list                Short and precise list of problems
                             o markdown            Markdown format
+                            o json                Json format (eslint-compatible)
     --noColor             Print results without color
     --outFile FILE        Emit all output to a single file
     --maxWarnings NUMBER  Fail only when the number of warnings is larger than this number
diff --git a/packages/lit-analyzer/src/lib/cli/format/json-formatter.ts b/packages/lit-analyzer/src/lib/cli/format/json-formatter.ts
new file mode 100644
index 00000000..398f2bdd
--- /dev/null
+++ b/packages/lit-analyzer/src/lib/cli/format/json-formatter.ts
@@ -0,0 +1,49 @@
+import { SourceFile } from "typescript";
+import { LitDiagnostic } from "../../analyze/types/lit-diagnostic.js";
+import { AnalysisStats, DiagnosticFormatter } from "./diagnostic-formatter.js";
+
+export class JsonDiagnosticFormatter implements DiagnosticFormatter {
+	protected diagnostics: { file: SourceFile; diagnostics: LitDiagnostic[] }[] = [];
+
+	report(_stats: AnalysisStats): string | undefined {
+		return JSON.stringify(
+			this.diagnostics.map(({ file, diagnostics }) => ({
+				filePath: file.fileName,
+				messages: diagnostics.map(diag => ({
+					ruleId: `lit-analyzer/${diag.source}`,
+					severity: diag.severity === "error" ? 2 : 1,
+					message: diag.message,
+					messageId: diag.code,
+					...this.diagnosticsFileLocation(diag)
+				})),
+				errorCount: diagnostics.filter(d => d.severity === "error").length,
+				// "fatalErrorCount": 0,
+				// "fixableErrorCount": 0,
+				warningCount: diagnostics.filter(d => d.severity === "warning").length,
+				// "fixableWarningCount": 0,
+				// "suppressedMessages": [],
+				// "usedDeprecatedRules": []
+				source: file.text
+			}))
+		);
+	}
+
+	diagnosticTextForFile(file: SourceFile, diagnostics: LitDiagnostic[]): string | undefined {
+		if (diagnostics.length === 0) return undefined;
+		this.diagnostics.push({ file, diagnostics });
+		return undefined;
+	}
+
+	protected diagnosticsFileLocation(diagnostic: LitDiagnostic) {
+		const fileToStart = diagnostic.file.text.slice(0, diagnostic.location.start).split("\n");
+		const startLine = fileToStart[fileToStart.length - 1];
+		const fileToEnd = diagnostic.file.text.slice(0, diagnostic.location.end).split("\n");
+		const endLine = fileToEnd[fileToEnd.length - 1];
+		return {
+			line: fileToStart.length,
+			column: startLine ? startLine.length + 1 : undefined,
+			endLine: fileToEnd.length,
+			endColumn: endLine ? endLine.length + 1 : undefined
+		};
+	}
+}
diff --git a/packages/lit-analyzer/src/lib/cli/lit-analyzer-cli-config.ts b/packages/lit-analyzer/src/lib/cli/lit-analyzer-cli-config.ts
index 0e0add52..6a3eb0a3 100644
--- a/packages/lit-analyzer/src/lib/cli/lit-analyzer-cli-config.ts
+++ b/packages/lit-analyzer/src/lib/cli/lit-analyzer-cli-config.ts
@@ -1,6 +1,6 @@
 import { LitAnalyzerRules } from "../analyze/lit-analyzer-config.js";
 
-export type FormatterFormat = "code" | "list" | "markdown";
+export type FormatterFormat = "code" | "list" | "markdown" | "json";
 
 export interface LitAnalyzerCliConfig {
 	debug?: boolean;