feat: enhance markdownToBlocks and customMarkdownConverter to support various code block language identifiers and improve serialization tests

src/editor/customMarkdownConverter.test.ts

@@ -2685,6 +2685,90 @@ describe("markdownToBlocks", () => {
       },
     ]);
   });
+
+  it("preserves opening-fence content when it is not a clean language identifier", () => {
+    const markdown = [
+      "```curl `http://localhost:3000/projects/classic-project/test/e1c1b38c/edit` \\",
+      "{{baseURL}}/endpoint?query_param_one=value_one&query_param_two=value_two",
+      "```",
+    ].join("\n");
+    const blocks = markdownToBlocks(markdown);
+    expect(blocks).toEqual([
+      {
+        type: "codeBlock",
+        props: { language: "" },
+        content: [
+          {
+            type: "text",
+            text: [
+              "curl `http://localhost:3000/projects/classic-project/test/e1c1b38c/edit` \\",
+              "{{baseURL}}/endpoint?query_param_one=value_one&query_param_two=value_two",
+            ].join("\n"),
+            styles: {},
+          },
+        ],
+        children: [],
+      },
+    ]);
+  });
+
+  it("round-trips an opening-fence-with-content code block to stable markdown", () => {
+    const markdown = [
+      "```curl `http://localhost:3000/projects/classic-project/test/e1c1b38c/edit` \\",
+      "{{baseURL}}/endpoint?query_param_one=value_one&query_param_two=value_two",
+      "```",
+    ].join("\n");
+    const blocks = markdownToBlocks(markdown);
+    const serialized = blocksToMarkdown(blocks as CustomEditorBlock[]);
+    expect(serialized).toBe(
+      [
+        "```",
+        "curl `http://localhost:3000/projects/classic-project/test/e1c1b38c/edit` \\",
+        "{{baseURL}}/endpoint?query_param_one=value_one&query_param_two=value_two",
+        "```",
+      ].join("\n"),
+    );
+    expect(markdownToBlocks(serialized)).toEqual(blocks);
+  });
+
+  it("preserves hyphenated language identifiers like shell-session", () => {
+    const markdown = ["```shell-session", "$ ls", "```"].join("\n");
+    const blocks = markdownToBlocks(markdown);
+    expect(blocks).toEqual([
+      {
+        type: "codeBlock",
+        props: { language: "shell-session" },
+        content: [{ type: "text", text: "$ ls", styles: {} }],
+        children: [],
+      },
+    ]);
+  });
+
+  it("preserves digit-prefixed language identifiers like 1c-enterprise", () => {
+    const markdown = ["```1c-enterprise", "code", "```"].join("\n");
+    const blocks = markdownToBlocks(markdown);
+    expect(blocks).toEqual([
+      {
+        type: "codeBlock",
+        props: { language: "1c-enterprise" },
+        content: [{ type: "text", text: "code", styles: {} }],
+        children: [],
+      },
+    ]);
+  });
+
+  it("sanitizes a malformed in-memory language prop on serialize", () => {
+    const blocks: CustomEditorBlock[] = [
+      {
+        id: "1",
+        type: "codeBlock",
+        props: { ...baseProps, language: "curl http://x" } as any,
+        content: [{ type: "text", text: "body", styles: {} }] as any,
+        children: [],
+      },
+    ];
+    expect(blocksToMarkdown(blocks)).toBe(["```", "body", "```"].join("\n"));
+  });
 });
 
 describe("file block serialization", () => {

src/editor/customMarkdownConverter.ts

@@ -334,7 +334,8 @@ function serializeBlock(
       return lines;
     }
     case "codeBlock": {
-      const language = (block.props as any).language || "";
+      const rawLanguage = (block.props as any).language || "";
+      const language = /[\s`]/.test(rawLanguage) ? "" : rawLanguage;
       const fence = "```" + language;
       const body = inlineContentToPlainText(block.content);
       lines.push(fence);
@@ -1290,8 +1291,16 @@ function parseCodeBlock(lines: string[], index: number): { block: CustomPartialB
     };
   }
 
-  const language = afterOpening.trim();
+  const info = afterOpening.trim();
+  let language = "";
   const body: string[] = [];
+  if (info.length > 0) {
+    if (/[\s`]/.test(info)) {
+      body.push(afterOpening);
+    } else {
+      language = info;
+    }
+  }
   let next = index + 1;
   while (next < lines.length && !lines[next].startsWith("```") ) {
     body.push(lines[next]);