From 8b08e67fdc9a3cd29c4b68ba914754040238a761 Mon Sep 17 00:00:00 2001
From: Elian Doran <contact@eliandoran.me>
Date: Sat, 22 Mar 2025 01:24:41 +0200
Subject: [PATCH] feat(linter/mermaid): better handling of zero position

---
 .../widgets/type_widgets/linters/mermaid.spec.ts  | 15 +++++++++------
 .../app/widgets/type_widgets/linters/mermaid.ts   | 10 +++++-----
 2 files changed, 14 insertions(+), 11 deletions(-)

diff --git a/src/public/app/widgets/type_widgets/linters/mermaid.spec.ts b/src/public/app/widgets/type_widgets/linters/mermaid.spec.ts
index 1d0808f30..458d1649a 100644
--- a/src/public/app/widgets/type_widgets/linters/mermaid.spec.ts
+++ b/src/public/app/widgets/type_widgets/linters/mermaid.spec.ts
@@ -21,22 +21,25 @@ describe("Mermaid linter", () => {
         expect(result[0].message).toSatisfy((v: string) => v.includes("Expecting 'SPACE'"));
         expect(result[0]).toMatchObject({
             from: { line: 0, col: 0 },
-            to: { line: 0, col: 0 }
+            to: { line: 0, col: 1 }
         });
     });
 
     it("reports correctly basic arrow missing in diagram", async () => {
         const input = trimIndentation`\
-            stateDiagram-v2
-            [*] -> Still
+            xychart-beta horizontal
+            title "Percentage usge"
+            x-axis [data, sys, usr, var]
+            y-axis 0--->100
+            bar [20, 70, 0, 0]
         `;
 
         const result = await validateMermaid(input);
         expect(result.length).toBe(1);
-        expect(result[0].message).toSatisfy((v: string) => v.includes("Expecting 'SPACE'"));
+        expect(result[0].message).toSatisfy((v: string) => v.includes("Expecting 'ARROW_DELIMITER'"));
         expect(result[0]).toMatchObject({
-            from: { line: 1, col: 0 },
-            to: { line: 1, col: 3 }
+            from: { line: 3, col: 8 },
+            to: { line: 3, col: 9 }
         });
     });
 });
diff --git a/src/public/app/widgets/type_widgets/linters/mermaid.ts b/src/public/app/widgets/type_widgets/linters/mermaid.ts
index 0df2ee824..34048ba60 100644
--- a/src/public/app/widgets/type_widgets/linters/mermaid.ts
+++ b/src/public/app/widgets/type_widgets/linters/mermaid.ts
@@ -31,12 +31,12 @@ export async function validateMermaid(text: string) {
 
         const mermaidError = (e as MermaidParseError);
         const loc = mermaidError.hash.loc;
-        let firstCol = loc.first_column;
-        let lastCol = loc.last_column;
 
-        if (firstCol !== 0 && lastCol !== 0) {
-            firstCol = lastCol + 1;
-            lastCol = firstCol + 1;
+        let firstCol = loc.first_column + 1;
+        let lastCol = loc.last_column + 1;
+
+        if (firstCol === 1 && lastCol === 1) {
+            firstCol = 0;
         }
 
         return [