From bb37848265f0cba474561e2235bfc1a10f1d4b8e Mon Sep 17 00:00:00 2001
From: Jeff Avallone <jeff.avallone@gmail.com>
Date: Sun, 18 Feb 2018 15:46:17 -0500
Subject: [PATCH] Adding specs and some refactoring for the Path#lineTo method

---
 .../__snapshots__/VerticalLayout.test.js.snap |  2 +-
 src/components/SVG/path.js                    | 29 ++++++++++++++-----
 src/components/SVG/path.test.js               | 27 +++++++++++++++++
 3 files changed, 50 insertions(+), 8 deletions(-)
 create mode 100644 src/components/SVG/path.test.js

diff --git a/src/components/SVG/__snapshots__/VerticalLayout.test.js.snap b/src/components/SVG/__snapshots__/VerticalLayout.test.js.snap
index b4efb8b..d24d22c 100644
--- a/src/components/SVG/__snapshots__/VerticalLayout.test.js.snap
+++ b/src/components/SVG/__snapshots__/VerticalLayout.test.js.snap
@@ -75,7 +75,7 @@ exports[`VerticalLayout rendering with connectors 1`] = `
   withConnectors={true}
 >
   <path
-    d="M10,60q0,-10 10,-10H20M130,60q0,-10 -10,-10H120M0,160c15,0 10,0 20,0H20M140,160c-15,0 -10,0 -20,0H120M10,260q0,10 10,10H20M130,260q0,10 -10,10H120M0,160q10,0 10,-10V60M140,160q-10,0 -10,-10V60M0,160q10,0 10,10V260M140,160q-10,0 -10,10V260"
+    d="M10,60q0,-10 10,-10M130,60q0,-10 -10,-10M0,160c15,0 10,0 20,0M140,160c-15,0 -10,0 -20,0M10,260q0,10 10,10M130,260q0,10 -10,10M0,160q10,0 10,-10V60M140,160q-10,0 -10,-10V60M0,160q10,0 10,10V260M140,160q-10,0 -10,10V260"
     style={
       Object {
         "fillOpacity": 0,
diff --git a/src/components/SVG/path.js b/src/components/SVG/path.js
index 7cde0e5..b39621b 100644
--- a/src/components/SVG/path.js
+++ b/src/components/SVG/path.js
@@ -26,22 +26,37 @@ class Path {
   }
 
   lineTo({ x, y, relative }) {
-    relative = relative === undefined ? this.relative : relative;
-    if (x !== undefined && (y === undefined || y === this.currentPosition.y)) {
+    if (relative === undefined) {
+      relative = this.relative;
+    }
+    if (x === undefined) {
+      x = relative ? 0 : this.currentPosition.x;
+    }
+    if (y === undefined) {
+      y = relative ? 0 : this.currentPosition.y;
+    }
+
+    if ((relative && x === 0 && y === 0)
+      || (!relative && x === this.currentPosition.x && y === this.currentPosition.y)) {
+      return this;
+    }
+
+    if (y === (relative ? 0 : this.currentPosition.y)) {
       const command = relative ? 'h' : 'H';
       this.pathParts.push(`${command}${x}`);
-      this.currentPosition.x = relative ? this.currentPosition.x + x : x;
-    } else if (y !== undefined && (x === undefined || x === this.currentPosition.x)) {
+    } else if (x === (relative ? 0 : this.currentPosition.x)) {
       const command = relative ? 'v' : 'V';
       this.pathParts.push(`${command}${y}`);
-      this.currentPosition.y = relative ? this.currentPosition.y + y : y;
     } else {
       const command = relative ? 'l' : 'L';
       this.pathParts.push(`${command}${x},${y}`);
-      this.currentPosition.x = relative ? this.currentPosition.x + x : x;
-      this.currentPosition.y = relative ? this.currentPosition.y + y : y;
     }
 
+    this.currentPosition = {
+      x: relative ? this.currentPosition.x + x : x,
+      y: relative ? this.currentPosition.y + y : y
+    };
+
     return this;
   }
 
diff --git a/src/components/SVG/path.test.js b/src/components/SVG/path.test.js
new file mode 100644
index 0000000..5457cf3
--- /dev/null
+++ b/src/components/SVG/path.test.js
@@ -0,0 +1,27 @@
+import Path from './path';
+
+describe('Path', () => {
+  [
+    // lineTo
+    [ 'lineTo', { x: 5, y: 1 }, 'L5,1' ],
+    [ 'lineTo', { x: 5, y: 0 }, 'H5'   ],
+    [ 'lineTo', { x: 0, y: 1 }, 'V1'   ],
+    [ 'lineTo', { x: 0, y: 0 }, ''     ],
+    [ 'lineTo', { x: 5 }, 'H5' ],
+    [ 'lineTo', { y: 1 }, 'V1' ],
+    [ 'lineTo', {}, '' ],
+    [ 'lineTo', { x: 5, y: 1, relative: true }, 'l5,1' ],
+    [ 'lineTo', { x: 5, y: 0, relative: true }, 'h5'   ],
+    [ 'lineTo', { x: 0, y: 1, relative: true }, 'v1'   ],
+    [ 'lineTo', { x: 0, y: 0, relative: true }, ''     ],
+    [ 'lineTo', { x: 5, relative: true }, 'h5' ],
+    [ 'lineTo', { y: 1, relative: true }, 'v1' ],
+    [ 'lineTo', { relative: true }, '' ],
+  ].forEach(([ cmd, args, str ], i) => (
+    test(`case #${ i }`, () => {
+      const path = new Path();
+      path[cmd](args);
+      expect(path.toString()).toEqual(str);
+    })
+  ));
+});