diff --git a/test/long-lines-negative-line-length.md b/test/long-lines-negative-line-length.md
new file mode 100644
index 00000000..14f2e335
--- /dev/null
+++ b/test/long-lines-negative-line-length.md
@@ -0,0 +1,12 @@
+# Long Lines Negative Line Length
+
+Text text text text text text text text text text text text text text text text text text text text.
+
+This is an invalid configuration, but present in the wild and (for backward compatibility) disables the rule:
+<https://github.com/electron/lint-roller/blob/1e062bda146160afb8eb232966287d5edb20e0a4/configs/markdownlint.json#L9>
+
+<!-- markdownlint-configure-file {
+  "line-length": {
+    "line_length": -1
+  }
+} -->
diff --git a/test/long-lines-thresholds.md b/test/long-lines-thresholds.md
new file mode 100644
index 00000000..256e017f
--- /dev/null
+++ b/test/long-lines-thresholds.md
@@ -0,0 +1,37 @@
+# Long Lines Thresholds
+
+00000000011111111112222222222333333333344444444445
+12345678901234567890123456789012345678901234567890
+
+Texxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx t
+
+Texxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx t
+
+{MD013:-2}
+
+## Texxxxxxxxxxxxxxxxxxxxxxxx t
+
+## Texxxxxxxxxxxxxxxxxxxxxxxxx t
+
+{MD013:-2}
+
+```text
+Texxxxxxxxxxxxxxxxx t
+Texxxxxxxxxxxxxxxxxx t
+```
+
+{MD013:-3}
+
+    Texxxxxxxxxxxxx t
+    Texxxxxxxxxxxxxx t
+
+{MD013:-2}
+
+<!-- markdownlint-configure-file {
+  "code-block-style": false,
+  "line-length": {
+    "line_length": 40,
+    "heading_line_length": 30,
+    "code_block_line_length": 20
+  }
+} -->
diff --git a/test/markdownlint-test.mjs b/test/markdownlint-test.mjs
index d8b73509..c4c74236 100644
--- a/test/markdownlint-test.mjs
+++ b/test/markdownlint-test.mjs
@@ -1101,7 +1101,7 @@ test("readme", async(t) => {
 });
 
 test("validateJsonUsingConfigSchemaStrict", async(t) => {
-  t.plan(220);
+  t.plan(221);
   // @ts-ignore
   const ajv = new Ajv(ajvOptions);
   const validateSchemaStrict = ajv.compile(configSchemaStrict);
@@ -1112,6 +1112,7 @@ test("validateJsonUsingConfigSchemaStrict", async(t) => {
     "test/inline-configure-file-invalid.md",
     "test/inline-configure-file-violations.md",
     "test/invalid-ul-style-style.md",
+    "test/long-lines-negative-line-length.md",
     "test/wrong-types-in-config-file.md"
   ]);
   const files = await globby([
diff --git a/test/snapshots/markdownlint-test-scenarios.mjs.md b/test/snapshots/markdownlint-test-scenarios.mjs.md
index 454a836b..400f3864 100644
--- a/test/snapshots/markdownlint-test-scenarios.mjs.md
+++ b/test/snapshots/markdownlint-test-scenarios.mjs.md
@@ -42078,6 +42078,27 @@ Generated by [AVA](https://avajs.dev).
       <!-- markdownlint-disable-file descriptive-link-text -->`,
     }
 
+## long-lines-negative-line-length.md
+
+> Snapshot 1
+
+    {
+      errors: [],
+      fixed: `# Long Lines Negative Line Length␊
+      ␊
+      Text text text text text text text text text text text text text text text text text text text text.␊
+      ␊
+      This is an invalid configuration, but present in the wild and (for backward compatibility) disables the rule:␊
+      <https://github.com/electron/lint-roller/blob/1e062bda146160afb8eb232966287d5edb20e0a4/configs/markdownlint.json#L9>␊
+      ␊
+      <!-- markdownlint-configure-file {␊
+        "line-length": {␊
+          "line_length": -1␊
+        }␊
+      } -->␊
+      `,
+    }
+
 ## long-lines-short-code.md
 
 > Snapshot 1
@@ -42637,6 +42658,121 @@ Generated by [AVA](https://avajs.dev).
       `,
     }
 
+## long-lines-thresholds.md
+
+> Snapshot 1
+
+    {
+      errors: [
+        {
+          errorContext: null,
+          errorDetail: 'Expected: 40; Actual: 42',
+          errorRange: [
+            41,
+            2,
+          ],
+          fixInfo: null,
+          lineNumber: 8,
+          ruleDescription: 'Line length',
+          ruleInformation: 'https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/md013.md',
+          ruleNames: [
+            'MD013',
+            'line-length',
+          ],
+          severity: 'error',
+        },
+        {
+          errorContext: null,
+          errorDetail: 'Expected: 30; Actual: 32',
+          errorRange: [
+            31,
+            2,
+          ],
+          fixInfo: null,
+          lineNumber: 14,
+          ruleDescription: 'Line length',
+          ruleInformation: 'https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/md013.md',
+          ruleNames: [
+            'MD013',
+            'line-length',
+          ],
+          severity: 'error',
+        },
+        {
+          errorContext: null,
+          errorDetail: 'Expected: 20; Actual: 22',
+          errorRange: [
+            21,
+            2,
+          ],
+          fixInfo: null,
+          lineNumber: 20,
+          ruleDescription: 'Line length',
+          ruleInformation: 'https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/md013.md',
+          ruleNames: [
+            'MD013',
+            'line-length',
+          ],
+          severity: 'error',
+        },
+        {
+          errorContext: null,
+          errorDetail: 'Expected: 20; Actual: 22',
+          errorRange: [
+            21,
+            2,
+          ],
+          fixInfo: null,
+          lineNumber: 26,
+          ruleDescription: 'Line length',
+          ruleInformation: 'https://github.com/DavidAnson/markdownlint/blob/v0.0.0/doc/md013.md',
+          ruleNames: [
+            'MD013',
+            'line-length',
+          ],
+          severity: 'error',
+        },
+      ],
+      fixed: `# Long Lines Thresholds␊
+      ␊
+      00000000011111111112222222222333333333344444444445␊
+      12345678901234567890123456789012345678901234567890␊
+      ␊
+      Texxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx t␊
+      ␊
+      Texxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx t␊
+      ␊
+      {MD013:-2}␊
+      ␊
+      ## Texxxxxxxxxxxxxxxxxxxxxxxx t␊
+      ␊
+      ## Texxxxxxxxxxxxxxxxxxxxxxxxx t␊
+      ␊
+      {MD013:-2}␊
+      ␊
+      \`\`\`text␊
+      Texxxxxxxxxxxxxxxxx t␊
+      Texxxxxxxxxxxxxxxxxx t␊
+      \`\`\`␊
+      ␊
+      {MD013:-3}␊
+      ␊
+          Texxxxxxxxxxxxx t␊
+          Texxxxxxxxxxxxxx t␊
+      ␊
+      {MD013:-2}␊
+      ␊
+      <!-- markdownlint-configure-file {␊
+        "code-block-style": false,␊
+        "line-length": {␊
+          "line_length": 40,␊
+          "heading_line_length": 30,␊
+          "code_block_line_length": 20␊
+        }␊
+      } -->␊
+      `,
+    }
+
 ## long_lines.md
 
 > Snapshot 1
diff --git a/test/snapshots/markdownlint-test-scenarios.mjs.snap b/test/snapshots/markdownlint-test-scenarios.mjs.snap
index f1350fa3..dbe674f4 100644
Binary files a/test/snapshots/markdownlint-test-scenarios.mjs.snap and b/test/snapshots/markdownlint-test-scenarios.mjs.snap differ