test warnings

test/assert.js

@@ -1,28 +1,67 @@
 import assert from "assert";
 
-function warns(run, expected) {
+function warns(run, expected = /warning/i) {
   const actual = [];
   const warn = console.warn;
+  let result;
   try {
     console.warn = (warning) => void actual.push(warning);
-    run();
-    assert.strictEqual(actual.length, 1);
+    result = run();
+    assert.strictEqual(actual.length, 1, "expected 1 warning");
     assert.match(actual[0], expected);
   } finally {
     console.warn = warn;
   }
+  return result;
+}
+
+async function warnsAsync(run, expected = /warning/i) {
+  const actual = [];
+  const warn = console.warn;
+  let result;
+  try {
+    console.warn = (warning) => void actual.push(warning);
+    result = await run();
+    assert.strictEqual(actual.length, 1, "expected 1 warning");
+    assert.match(actual[0], expected);
+  } finally {
+    console.warn = warn;
+  }
+  return result;
 }
 
 function doesNotWarn(run) {
   const actual = [];
   const warn = console.warn;
+  let result;
+  try {
+    console.warn = (warning) => void actual.push(warning);
+    result = run();
+    assert.strictEqual(actual.length, 0, "expected 0 warnings");
+  } finally {
+    console.warn = warn;
+  }
+  return result;
+}
+
+async function doesNotWarnAsync(run) {
+  const actual = [];
+  const warn = console.warn;
+  let result;
   try {
     console.warn = (warning) => void actual.push(warning);
-    run();
-    assert.strictEqual(actual.length, 0);
+    result = await run();
+    assert.strictEqual(actual.length, 0, "expected 0 warnings");
   } finally {
     console.warn = warn;
   }
+  return result;
 }
 
-export default {...assert, warns, doesNotWarn};
+export default {
+  ...assert,
+  warns,
+  warnsAsync,
+  doesNotWarn,
+  doesNotWarnAsync
+};

test/plot.js

@@ -1,13 +1,13 @@
-import assert from "assert";
 import {promises as fs} from "fs";
 import * as path from "path";
 import beautify from "js-beautify";
+import assert from "./assert.js";
 import it from "./jsdom.js";
 import * as plots from "./plots/index.js";
 
 for (const [name, plot] of Object.entries(plots)) {
   it(`plot ${name}`, async () => {
-    const root = await plot();
+    const root = await (name.startsWith("warn") ? assert.warnsAsync : assert.doesNotWarnAsync)(plot);
     const ext = root.tagName === "svg" ? "svg" : "html";
     for (const svg of root.tagName === "svg" ? [root] : root.querySelectorAll("svg")) {
       svg.setAttributeNS("http://www.w3.org/2000/xmlns/", "xmlns", "http://www.w3.org/2000/svg");
@@ -59,7 +59,7 @@ for (const [name, plot] of Object.entries(plots)) {
       await fs.writeFile(diffile, actual, "utf8");
     }
 
-    assert(equal, `${name} must match snapshot`);
+    assert.ok(equal, `${name} must match snapshot`);
   });
 }
 

test/plots/color-misaligned.ts

@@ -1,31 +1,31 @@
 import * as Plot from "@observablehq/plot";
 import * as d3 from "d3";
 
-export function colorMisalignedDivergingDomain() {
+export function warnMisalignedDivergingDomain() {
   return Plot.cellX(d3.range(-5, 6), {x: Plot.identity, fill: Plot.identity}).plot({
     color: {legend: true, type: "diverging", domain: [-5, 5, 10]}
   });
 }
 
-export function colorMisalignedLinearDomain() {
+export function warnMisalignedLinearDomain() {
   return Plot.cellX(d3.range(11), {fill: Plot.identity}).plot({
     color: {legend: true, type: "linear", domain: [0, 10, 20], range: ["red", "blue"]}
   });
 }
 
-export function colorMisalignedLinearDomainReverse() {
+export function warnMisalignedLinearDomainReverse() {
   return Plot.cellX(d3.range(11), {fill: Plot.identity}).plot({
     color: {legend: true, type: "linear", domain: [0, 10, 20], reverse: true, range: ["red", "blue"]}
   });
 }
 
-export function colorMisalignedLinearRange() {
+export function warnMisalignedLinearRange() {
   return Plot.cellX(d3.range(11), {fill: Plot.identity}).plot({
     color: {legend: true, type: "linear", domain: [0, 10], range: ["red", "blue", "green"]}
   });
 }
 
-export function colorMisalignedLinearRangeReverse() {
+export function warnMisalignedLinearRangeReverse() {
   return Plot.cellX(d3.range(11), {fill: Plot.identity}).plot({
     color: {legend: true, type: "linear", domain: [0, 10], reverse: true, range: ["red", "blue", "green"]}
   });

test/scales/scales-test.js

@@ -1,6 +1,6 @@
 import * as Plot from "@observablehq/plot";
 import * as d3 from "d3";
-import assert from "assert";
+import assert from "../assert.js";
 import it from "../jsdom.js";
 
 it("Plot throws an error if an ordinal position scale has a huge inferred domain", () => {
@@ -411,7 +411,10 @@ it("plot(…).scale(name) handles a reversed diverging scale with a descending d
 });
 
 it("plot(…).scale(name) ignores extra domain elements with a diverging scale", async () => {
-  const plot = Plot.plot({color: {type: "diverging", domain: [-5, 5, 10]}});
+  const plot = assert.warns(
+    () => Plot.plot({color: {type: "diverging", domain: [-5, 5, 10]}}),
+    /domain contains extra/
+  );
   const {interpolate, ...color} = plot.scale("color");
   scaleEqual(color, {
     type: "diverging",
@@ -722,9 +725,13 @@ it("plot(…).scale('color') can return a “polylinear” piecewise linear scal
 });
 
 it("plot(…).scale('color') ignores extra domain elements with an explicit range", () => {
-  const plot = Plot.cellX([100, 200, 300, 400], {fill: Plot.identity}).plot({
-    color: {type: "linear", domain: [0, 100, 200], range: ["red", "blue"]}
-  });
+  const plot = assert.warns(
+    () =>
+      Plot.cellX([100, 200, 300, 400], {fill: Plot.identity}).plot({
+        color: {type: "linear", domain: [0, 100, 200], range: ["red", "blue"]}
+      }),
+    /domain contains extra/
+  );
   scaleEqual(plot.scale("color"), {
     type: "linear",
     domain: [0, 100],
@@ -735,9 +742,13 @@ it("plot(…).scale('color') ignores extra domain elements with an explicit rang
 });
 
 it("plot(…).scale('color') ignores extra range elements with an explicit range", () => {
-  const plot = Plot.cellX([100, 200, 300, 400], {fill: Plot.identity}).plot({
-    color: {type: "linear", domain: [0, 100], range: ["red", "blue", "green"]}
-  });
+  const plot = assert.warns(
+    () =>
+      Plot.cellX([100, 200, 300, 400], {fill: Plot.identity}).plot({
+        color: {type: "linear", domain: [0, 100], range: ["red", "blue", "green"]}
+      }),
+    /range contains extra/
+  );
   scaleEqual(plot.scale("color"), {
     type: "linear",
     domain: [0, 100],
@@ -748,9 +759,13 @@ it("plot(…).scale('color') ignores extra range elements with an explicit range
 });
 
 it("plot(…).scale('color') ignores extra domain elements with an explicit range when reversed", () => {
-  const plot = Plot.cellX([100, 200, 300, 400], {fill: Plot.identity}).plot({
-    color: {type: "linear", domain: [0, 100, 200], range: ["red", "blue"], reverse: true}
-  });
+  const plot = assert.warns(
+    () =>
+      Plot.cellX([100, 200, 300, 400], {fill: Plot.identity}).plot({
+        color: {type: "linear", domain: [0, 100, 200], range: ["red", "blue"], reverse: true}
+      }),
+    /domain contains extra/
+  );
   scaleEqual(plot.scale("color"), {
     type: "linear",
     domain: [100, 0],
@@ -761,9 +776,13 @@ it("plot(…).scale('color') ignores extra domain elements with an explicit rang
 });
 
 it("plot(…).scale('color') ignores extra range elements with an explicit range when reversed", () => {
-  const plot = Plot.cellX([100, 200, 300, 400], {fill: Plot.identity}).plot({
-    color: {type: "linear", domain: [0, 100], range: ["red", "blue", "green"], reverse: true}
-  });
+  const plot = assert.warns(
+    () =>
+      Plot.cellX([100, 200, 300, 400], {fill: Plot.identity}).plot({
+        color: {type: "linear", domain: [0, 100], range: ["red", "blue", "green"], reverse: true}
+      }),
+    /range contains extra/
+  );
   scaleEqual(plot.scale("color"), {
     type: "linear",
     domain: [100, 0],