fix: add codeContext property to types

index.d.ts

@@ -1,6 +1,21 @@
 declare module "youch" {
+
+  interface YouchOptionsContract {
+    /**
+     * Number of lines to be displayed above the error
+     * in the stack trace.
+     */
+    preLines?: number;
+
+    /**
+     * Number of lines to be displayed below the error
+     * in the stack trace.
+     */
+    postLines?: number;
+  }
+
   class Youch<Error, Request> {
-    constructor(error: Error, request: Request);
+    constructor(error: Error, request: Request, options?: YouchOptionsContract);
 
     /**
      * Stores the link `callback` which
@@ -18,21 +33,21 @@ declare module "youch" {
         name: string;
         status: number;
         frames: {
-          file: string,
-          filePath: string,
-          line: number,
-          column: number,
-          callee: string,
-          calleeShort: string,
+          file: string;
+          filePath: string;
+          line: number;
+          column: number;
+          callee: string;
+          calleeShort: string;
           context: {
-            start: number,
-            pre: string,
-            line: string,
-            post: string,
-          },
-          isModule: boolean,
-          isNative: boolean,
-          isApp: boolean
+            start: number;
+            pre: string;
+            line: string;
+            post: string;
+          };
+          isModule: boolean;
+          isNative: boolean;
+          isApp: boolean;
         }[];
       };
     }>;

src/Youch.js

@@ -20,8 +20,11 @@ const VIEW_PATH = './error.compiled.mustache'
 const viewTemplate = fs.readFileSync(path.join(__dirname, VIEW_PATH), 'utf-8')
 
 class Youch {
-  constructor (error, request) {
-    this.codeContext = 5
+  constructor (error, request, options = {}) {
+    this.options = options
+    this.options.postLines = options.postLines || 5
+    this.options.preLines = options.preLines || 5
+
     this._filterHeaders = ['cookie', 'connection']
     this.error = error
     this.request = request
@@ -64,11 +67,11 @@ class Youch {
 
         resolve({
           pre: lines.slice(
-            Math.max(0, lineNumber - (this.codeContext + 1)),
+            Math.max(0, lineNumber - (this.options.preLines + 1)),
             lineNumber - 1
           ),
           line: lines[lineNumber - 1],
-          post: lines.slice(lineNumber, lineNumber + this.codeContext)
+          post: lines.slice(lineNumber, lineNumber + this.options.postLines)
         })
       })
     })

test/youch.spec.js

@@ -174,4 +174,43 @@ test.group('Youch', () => {
       done()
     })
   })
+
+  test('preLines/postLines should be affect number of frame context lines', (assert, done) => {
+    const error = new Error('this is bar')
+
+    const youch = new Youch(error, {}, {
+      preLines: 2,
+      postLines: 4
+    })
+
+    youch
+      ._parseError()
+      .then((stack) => {
+        const frame = stack[0]
+        const context = youch._getContext(frame)
+
+        assert.equal(context.pre.split('\n').length, 2)
+        assert.equal(context.post.split('\n').length, 4)
+        done()
+      })
+      .catch(done)
+  })
+
+  test('default preLines/postLines should be 5', (assert, done) => {
+    const error = new Error('this is bar')
+
+    const youch = new Youch(error, {})
+
+    youch
+      ._parseError()
+      .then((stack) => {
+        const frame = stack[0]
+        const context = youch._getContext(frame)
+
+        assert.equal(context.pre.split('\n').length, 5)
+        assert.equal(context.post.split('\n').length, 5)
+        done()
+      })
+      .catch(done)
+  })
 })

test/youch.spec.mjs

@@ -179,4 +179,43 @@ test.group('Youch | ESM', () => {
       done()
     })
   })
+
+  test('preLines/postLines should be affect number of frame context lines', (assert, done) => {
+    const error = new Error('this is bar')
+
+    const youch = new Youch(error, {}, {
+      preLines: 2,
+      postLines: 4
+    })
+
+    youch
+      ._parseError()
+      .then((stack) => {
+        const frame = stack[0]
+        const context = youch._getContext(frame)
+
+        assert.equal(context.pre.split('\n').length, 2)
+        assert.equal(context.post.split('\n').length, 4)
+        done()
+      })
+      .catch(done)
+  })
+
+  test('default preLines/postLines should be 5', (assert, done) => {
+    const error = new Error('this is bar')
+
+    const youch = new Youch(error, {})
+
+    youch
+      ._parseError()
+      .then((stack) => {
+        const frame = stack[0]
+        const context = youch._getContext(frame)
+
+        assert.equal(context.pre.split('\n').length, 5)
+        assert.equal(context.post.split('\n').length, 5)
+        done()
+      })
+      .catch(done)
+  })
 })