Fix #59.

rollup.config.js

@@ -11,7 +11,7 @@ const config = {
     indent: false,
     extend: true,
     banner: `// ${meta.homepage} v${meta.version} Copyright ${(new Date).getFullYear()} ${meta.author.name}`,
-    globals: Object.assign({}, ...Object.keys(meta.dependencies || {}).filter(key => /^d3-/.test(key)).map(key => ({[key]: "d3"})))
+    globals: Object.assign({}, ...Object.keys({...meta.dependencies, ...meta.peerDependencies}).filter(key => /^d3-/.test(key)).map(key => ({[key]: "d3"})))
   },
   plugins: []
 };

src/selection/transition.js

@@ -14,7 +14,7 @@ function inherit(node, id) {
   var timing;
   while (!(timing = node.__transition) || !(timing = timing[id])) {
     if (!(node = node.parentNode)) {
-      return defaultTiming.time = now(), defaultTiming;
+      throw new Error(`transition ${id} not found`);
     }
   }
   return timing;

test/selection/transition-test.js

@@ -129,3 +129,24 @@ tape("selection.transition(transition) reselects the existing transition with th
   test.equal(transition2.tween("tween"), bar);
   test.end();
 });
+
+tape("selection.transition(transition) throws an error if the specified transition is not found", function(test) {
+  var document = jsdom("<h1 id='one'></h1><h1 id='two'></h1>"),
+      one = document.querySelector("#one"),
+      two = document.querySelector("#two"),
+      transition1 = d3_selection.select(one).transition(),
+      transition2 = d3_selection.select(two).transition().delay(50);
+  try {
+    d3_selection.select(two).transition(transition1);
+    test.fail();
+  } catch (error) {
+    test.deepEqual(error.message, `transition ${transition1._id} not found`);
+  }
+  try {
+    d3_selection.select(one).transition(transition2);
+    test.fail();
+  } catch (error) {
+    test.deepEqual(error.message, `transition ${transition2._id} not found`);
+  }
+  test.end();
+});

test/transition/delay-test.js

@@ -18,8 +18,6 @@ tape("transition.delay() returns the delay for the first non-null node", functio
   test.strictEqual(d3_selection.select(two).transition(transition2).delay(), 50);
   test.strictEqual(d3_selection.selectAll([null, one]).transition(transition1).delay(), 0);
   test.strictEqual(d3_selection.selectAll([null, two]).transition(transition2).delay(), 50);
-  test.strictEqual(d3_selection.selectAll([one, two]).transition(transition1).delay(), 0);
-  test.strictEqual(d3_selection.selectAll([two, one]).transition(transition2).delay(), 50);
   test.end();
 });
 

test/transition/duration-test.js

@@ -18,8 +18,6 @@ tape("transition.duration() returns the duration for the first non-null node", f
   test.strictEqual(d3_selection.select(two).transition(transition2).duration(), 50);
   test.strictEqual(d3_selection.selectAll([null, one]).transition(transition1).duration(), 250);
   test.strictEqual(d3_selection.selectAll([null, two]).transition(transition2).duration(), 50);
-  test.strictEqual(d3_selection.selectAll([one, two]).transition(transition1).duration(), 250);
-  test.strictEqual(d3_selection.selectAll([two, one]).transition(transition2).duration(), 50);
   test.end();
 });
 

test/transition/ease-test.js

@@ -21,8 +21,6 @@ tape("transition.ease() returns the easing function for the first non-null node"
   test.strictEqual(d3_selection.select(two).transition(transition2).ease(), d3_ease.easeBounce);
   test.strictEqual(d3_selection.selectAll([null, one]).transition(transition1).ease(), d3_ease.easeCubic);
   test.strictEqual(d3_selection.selectAll([null, two]).transition(transition2).ease(), d3_ease.easeBounce);
-  test.strictEqual(d3_selection.selectAll([one, two]).transition(transition1).ease(), d3_ease.easeCubic);
-  test.strictEqual(d3_selection.selectAll([two, one]).transition(transition2).ease(), d3_ease.easeBounce);
   test.end();
 });
 

test/transition/merge-test.js

@@ -7,8 +7,9 @@ tape("transition.merge(other) merges elements from the specified other transitio
   var document = jsdom("<h1 id='one'></h1><h1 id='two'></h1>"),
       one = document.querySelector("#one"),
       two = document.querySelector("#two"),
-      transition1 = d3_selection.selectAll([null, two]).transition(),
-      transition2 = d3_selection.selectAll([one, null]).transition(transition1),
+      transition0 = d3_selection.select(document.documentElement).transition(),
+      transition1 = d3_selection.selectAll([null, two]).transition(transition0),
+      transition2 = d3_selection.selectAll([one, null]).transition(transition0),
       transition3 = transition1.merge(transition2);
   test.equal(transition3 instanceof d3_transition.transition, true);
   test.deepEqual(transition3._groups, [[one, two]]);