[TS dashboard] Draw dependencies between files (#17338)

If you're thinking about converting a file to TypeScript, you might want
to know what files import that file and what files it imports. This
commit makes it so that if you click on a box in the visualization, it
will draw lines between that box and the other boxes which represent its
dependents and dependencies.

Co-authored-by: legobeat <109787230+legobeat@users.noreply.github.com>

development/ts-migration-dashboard/app/components/App.tsx

@@ -1,7 +1,9 @@
-import React from 'react';
+import React, { useState } from 'react';
-import classnames from 'classnames';
-import { Tooltip as ReactTippy } from 'react-tippy';
 import { readPartitionsFile } from '../../common/partitions-file';
+import type { ModulePartitionChild } from '../../common/build-module-partitions';
+import Box from './Box';
+import Connections from './Connections';
+import type { BoxRect, BoxModel } from './types';
 
 type Summary = {
   numConvertedModules: number;
@@ -12,18 +14,87 @@ function calculatePercentageComplete(summary: Summary) {
   return ((summary.numConvertedModules / summary.numModules) * 100).toFixed(1);
 }
 
-export default function App() {
 const partitions = readPartitionsFile();
-
 const allModules = partitions.flatMap((partition) => {
   return partition.children;
 });
+const modulesById = allModules.reduce<Record<string, ModulePartitionChild>>(
+  (obj, module) => {
+    return { ...obj, [module.id]: module };
+  },
+  {},
+);
 const overallTotal = {
   numConvertedModules: allModules.filter((module) => module.hasBeenConverted)
     .length,
   numModules: allModules.length,
 };
 
+export default function App() {
+  const [boxRectsByModuleId, setBoxRectsById] = useState<Record<
+    string,
+    BoxRect
+  > | null>(null);
+  const boxesByModuleId =
+    boxRectsByModuleId === null
+      ? {}
+      : Object.values(boxRectsByModuleId).reduce<Record<string, BoxModel>>(
+          (obj, boxRect) => {
+            const module = modulesById[boxRect.moduleId];
+
+            const dependencyBoxRects = module.dependencyIds.reduce<BoxRect[]>(
+              (dependencyBoxes, dependencyId) => {
+                if (boxRectsByModuleId[dependencyId] === undefined) {
+                  return dependencyBoxes;
+                }
+                return [...dependencyBoxes, boxRectsByModuleId[dependencyId]];
+              },
+              [],
+            );
+
+            const dependentBoxRects = module.dependentIds.reduce<BoxRect[]>(
+              (dependentBoxes, dependentId) => {
+                if (boxRectsByModuleId[dependentId] === undefined) {
+                  return dependentBoxes;
+                }
+                return [...dependentBoxes, boxRectsByModuleId[dependentId]];
+              },
+              [],
+            );
+
+            return {
+              ...obj,
+              [boxRect.moduleId]: {
+                rect: boxRect,
+                dependencyBoxRects,
+                dependentBoxRects,
+              },
+            };
+          },
+          {},
+        );
+  const [activeBoxRectId, setActiveBoxRectId] = useState<string | null>(null);
+  const activeBoxRect =
+    boxRectsByModuleId === null || activeBoxRectId === null
+      ? null
+      : boxRectsByModuleId[activeBoxRectId];
+
+  const registerBox = (id: string, boxRect: BoxRect) => {
+    setBoxRectsById((existingBoxRectsById) => {
+      if (existingBoxRectsById === undefined) {
+        return { [id]: boxRect };
+      }
+      return { ...existingBoxRectsById, [id]: boxRect };
+    });
+  };
+  const toggleConnectionsFor = (id: string) => {
+    if (activeBoxRectId !== undefined && activeBoxRectId === id) {
+      setActiveBoxRectId(null);
+    } else {
+      setActiveBoxRectId(id);
+    }
+  };
+
   return (
     <>
       <h1 className="page-header">
@@ -50,17 +121,35 @@ export default function App() {
           </p>
 
           <p>
-            Each box
+            Each box on this page represents a file in the codebase. Gray boxes
-            <div className="module module--inline module--to-be-converted">
+            <span className="module module--inline module--to-be-converted">
               &nbsp;
-            </div>
+            </span>
-            on this page represents a file that either we want to convert or
+            represent files that need to be converted to TypeScript. Green boxes
-            we've already converted to TypeScript (hover over a box to see the
+            <span className="module module--inline module--has-been-converted">
-            filename). Boxes that are
-            <div className="module module--inline module--to-be-converted module--test">
               &nbsp;
-            </div>
+            </span>
-            greyed out are test or Storybook files.
+            are files that have already been converted. Faded boxes
+            <span className="module module--inline module--to-be-converted module--test">
+              &nbsp;
+            </span>
+            <span
+              className="module module--inline module--has-been-converted module--test"
+              style={{ marginLeft: 0 }}
+            >
+              &nbsp;
+            </span>
+            are test or Storybook files.
+          </p>
+
+          <p>
+            You can hover over a box to see the name of the file that it
+            represents. You can also click on a box to see connections between
+            other files;{' '}
+            <strong className="module-connection__dependency">red</strong> lines
+            lead to dependencies (other files that import the file);{' '}
+            <strong className="module-connection__dependent">blue</strong> lines
+            lead to dependents (other files that are imported by the file).
           </p>
 
           <p>
@@ -103,36 +192,25 @@ export default function App() {
             <div key={partition.level} className="partition">
               <div className="partition__name">level {partition.level}</div>
               <div className="partition__children">
-                {partition.children.map(({ name, hasBeenConverted }) => {
+                {partition.children.map((module) => {
-                  const isTest = /\.test\.(?:js|tsx?)/u.test(name);
+                  const areConnectionsVisible = activeBoxRectId === module.id;
-                  const isStorybookModule = /\.stories\.(?:js|tsx?)/u.test(
-                    name,
-                  );
                   return (
-                    <ReactTippy
+                    <Box
-                      key={name}
+                      key={module.id}
-                      title={name}
+                      module={module}
-                      arrow={true}
+                      register={registerBox}
-                      animation="fade"
+                      toggleConnectionsFor={toggleConnectionsFor}
-                      duration={250}
+                      areConnectionsVisible={areConnectionsVisible}
-                      className="module__tooltipped"
-                      style={{ display: 'block' }}
-                    >
-                      <div
-                        className={classnames('module', {
-                          'module--has-been-converted': hasBeenConverted,
-                          'module--to-be-converted': !hasBeenConverted,
-                          'module--test': isTest,
-                          'module--storybook': isStorybookModule,
-                        })}
                     />
-                    </ReactTippy>
                   );
                 })}
               </div>
             </div>
           );
         })}
+        {activeBoxRect === null ? null : (
+          <Connections activeBox={boxesByModuleId[activeBoxRect.moduleId]} />
+        )}
       </div>
     </>
   );

development/ts-migration-dashboard/app/components/Box.tsx

@@ -0,0 +1,69 @@
+import React, { useEffect, useRef } from 'react';
+import classnames from 'classnames';
+import { Tooltip as ReactTippy } from 'react-tippy';
+import type { ModulePartitionChild } from '../../common/build-module-partitions';
+import type { BoxRect } from './types';
+
+export default function Box({
+  module,
+  register,
+  toggleConnectionsFor,
+  areConnectionsVisible,
+}: {
+  module: ModulePartitionChild;
+  register: (id: string, boxRect: BoxRect) => void;
+  toggleConnectionsFor: (id: string) => void;
+  areConnectionsVisible: boolean;
+}) {
+  const isTest = /\.test\.(?:js|tsx?)/u.test(module.id);
+  const isStorybookModule = /\.stories\.(?:js|tsx?)/u.test(module.id);
+  const ref = useRef<HTMLDivElement>(null);
+
+  useEffect(() => {
+    if (ref.current?.offsetParent) {
+      const rect = ref.current.getBoundingClientRect();
+      const offsetParentRect = ref.current.offsetParent.getBoundingClientRect();
+      const top = rect.top - offsetParentRect.top;
+      const left = rect.left - offsetParentRect.left;
+      const centerX = left + rect.width / 2;
+      const centerY = top + rect.height / 2;
+      register(module.id, {
+        moduleId: module.id,
+        top,
+        left,
+        width: rect.width,
+        height: rect.height,
+        centerX,
+        centerY,
+      });
+    }
+  }, [ref]);
+
+  const onClick = (event: React.MouseEvent<HTMLDivElement>) => {
+    event.preventDefault();
+    toggleConnectionsFor(module.id);
+  };
+
+  return (
+    <ReactTippy
+      title={module.id}
+      arrow={true}
+      animation="fade"
+      duration={250}
+      className="module__tooltipped"
+      style={{ display: 'block' }}
+    >
+      <div
+        ref={ref}
+        onClick={onClick}
+        className={classnames('module', {
+          'module--has-been-converted': module.hasBeenConverted,
+          'module--to-be-converted': !module.hasBeenConverted,
+          'module--test': isTest,
+          'module--storybook': isStorybookModule,
+          'module--active': areConnectionsVisible,
+        })}
+      />
+    </ReactTippy>
+  );
+}

development/ts-migration-dashboard/app/components/Connections.tsx

@@ -0,0 +1,143 @@
+import React from 'react';
+import type { BoxModel } from './types';
+
+function buildShapePoints(coordinates: [number, number][]): string {
+  return coordinates.map(([x, y]) => `${x},${y}`).join(' ');
+}
+
+function buildPathD(coordinates: [number, number][]): string {
+  return coordinates
+    .map(([x, y], index) => {
+      if (index === 0) {
+        return `M ${x},${y}`;
+      }
+      return `L ${x},${y}`;
+    })
+    .join(' ');
+}
+
+function Arrowhead({
+  type,
+  x,
+  y,
+}: {
+  type: 'dependency' | 'dependent';
+  x: number;
+  y: number;
+}) {
+  return (
+    <polygon
+      className={`module-connection__${type}-arrowhead`}
+      points={buildShapePoints([
+        [x - 6, y - 6],
+        [x + 6, y - 6],
+        [x, y],
+      ])}
+    />
+  );
+}
+
+function Line({
+  type,
+  originX,
+  originY,
+  originYOffset = 0,
+  destinationX,
+  destinationY,
+  destinationYOffset = 0,
+}: {
+  type: 'dependency' | 'dependent';
+  originX: number;
+  originY: number;
+  originYOffset?: number;
+  destinationX: number;
+  destinationY: number;
+  destinationYOffset?: number;
+}) {
+  const coordinates: [number, number][] =
+    type === 'dependency'
+      ? [
+          [originX, originY],
+          [originX, originY + originYOffset],
+          [destinationX, originY + originYOffset],
+          [destinationX, destinationY],
+        ]
+      : [
+          [originX, originY],
+          [originX, destinationY - destinationYOffset],
+          [destinationX, destinationY - destinationYOffset],
+          [destinationX, destinationY],
+        ];
+  return (
+    <path
+      className={`module-connection__${type}`}
+      d={buildPathD(coordinates)}
+    />
+  );
+}
+
+function LineStart({
+  type,
+  x,
+  y,
+}: {
+  type: 'dependency' | 'dependent';
+  x: number;
+  y: number;
+}) {
+  return (
+    <circle className={`module-connection__${type}-point`} cx={x} cy={y} />
+  );
+}
+
+export default function Connections({ activeBox }: { activeBox: BoxModel }) {
+  return (
+    <svg className="module-connections">
+      {activeBox.dependencyBoxRects.length === 0 ? null : (
+        <Arrowhead
+          type="dependency"
+          x={activeBox.rect.centerX}
+          y={activeBox.rect.centerY}
+        />
+      )}
+      {activeBox.dependencyBoxRects.map((dependencyBoxRect) => {
+        return (
+          <React.Fragment key={dependencyBoxRect.moduleId}>
+            <Line
+              type="dependency"
+              originX={dependencyBoxRect.centerX}
+              originY={dependencyBoxRect.centerY}
+              originYOffset={dependencyBoxRect.height / 2 + 7}
+              destinationX={activeBox.rect.centerX}
+              destinationY={activeBox.rect.centerY}
+            />
+            <LineStart
+              type="dependency"
+              x={dependencyBoxRect.centerX}
+              y={dependencyBoxRect.centerY}
+            />
+          </React.Fragment>
+        );
+      })}
+      {activeBox.dependentBoxRects.map((dependentBoxRect) => {
+        return (
+          <React.Fragment key={dependentBoxRect.moduleId}>
+            <Line
+              type="dependent"
+              originX={activeBox.rect.centerX}
+              originY={activeBox.rect.centerY}
+              destinationX={dependentBoxRect.centerX}
+              destinationY={dependentBoxRect.centerY}
+              destinationYOffset={dependentBoxRect.height / 2 + 7}
+            />
+            <Arrowhead
+              type="dependent"
+              x={dependentBoxRect.centerX}
+              y={dependentBoxRect.centerY}
+            />
+          </React.Fragment>
+        );
+      })}
+    </svg>
+  );
+}

development/ts-migration-dashboard/app/components/types.ts

@@ -0,0 +1,15 @@
+export type BoxRect = {
+  moduleId: string;
+  top: number;
+  left: number;
+  width: number;
+  height: number;
+  centerX: number;
+  centerY: number;
+};
+
+export type BoxModel = {
+  rect: BoxRect;
+  dependencyBoxRects: BoxRect[];
+  dependentBoxRects: BoxRect[];
+};

development/ts-migration-dashboard/app/styles/custom-elements.scss

@@ -2,6 +2,10 @@
   --blue-gray-350: hsl(209deg 13.7% 62.4%);
   --blue-gray-100: hsl(209.8deg 16.5% 89%);
   --green: hsl(113deg 100% 38%);
+  --red: hsl(13deg 98% 61%);
+  --blue: hsl(246deg 97% 55%);
+  --light-cyan: hsl(178deg 100% 85%);
+  --cyan: hsl(178deg 100% 42%);
 }
 
 .page-header {
@@ -69,6 +73,10 @@
   border: 1px solid rgb(0 0 0 / 50%);
 }
 
+.partitions {
+  position: relative;
+}
+
 .partition {
   display: flex;
   gap: 0.5rem;
@@ -94,8 +102,9 @@
 .module {
   width: 1.5rem;
   height: 1.5rem;
-  border: 1px solid rgba(0 0 0 / 25%);
+  border: 1px solid hsla(0deg 0% 0% / 25%);
   border-radius: 0.25rem;
+  cursor: pointer;
 
   &--inline {
     display: inline-block;
@@ -120,6 +129,55 @@
   &--storybook {
     opacity: 0.3;
   }
+
+  &--active {
+    border-color: var(--cyan);
+    background-color: var(--light-cyan);
+    border-width: 2px;
+  }
+}
+
+.module-connections {
+  width: 100%;
+  height: 100%;
+  position: absolute;
+  top: 0;
+  left: 0;
+  pointer-events: none;
+}
+
+.module-connection {
+  &__dependency-arrowhead {
+    fill: var(--red);
+  }
+
+  &__dependency {
+    fill: none;
+    stroke: var(--red);
+    color: var(--red);
+    stroke-width: 2px;
+  }
+
+  &__dependency-point {
+    fill: var(--red);
+    r: 3px;
+  }
+
+  &__dependent-arrowhead {
+    fill: var(--blue);
+  }
+
+  &__dependent {
+    fill: none;
+    stroke: var(--blue);
+    color: var(--blue);
+    stroke-width: 2px;
+  }
+
+  &__dependent-point {
+    fill: var(--blue);
+    r: 3px;
+  }
 }
 
 /* Package overrides */

development/ts-migration-dashboard/common/build-module-partitions.ts

@@ -9,24 +9,42 @@ import {
 } from './constants';
 
 /**
- * Represents a module that has been imported somewhere in the codebase.
+ * Represents a module that has been imported somewhere in the codebase, whether
+ * it is local to the project or an NPM package.
  *
- * @property id - The name of a file or NPM module.
+ * @property id - If an NPM package, then the name of the package; otherwise the
+ * path to a file within the project.
  * @property dependents - The modules which are imported by this module.
  * @property level - How many modules it takes to import this module (from the
  * root of the dependency tree).
- * @property isExternal - Whether the module refers to a NPM module.
+ * @property isExternal - Whether the module refers to a NPM package.
  * @property hasBeenConverted - Whether the module was one of the files we
  * wanted to convert to TypeScript and has been converted.
  */
 type Module = {
   id: string;
   dependents: Module[];
+  dependencies: Module[];
   level: number;
   isExternal: boolean;
   hasBeenConverted: boolean;
 };
 
+/**
+ * Represents a module that belongs to a certain level within the dependency
+ * graph, displayed as a box in the UI.
+ *
+ * @property id - The id of the module.
+ * @property hasBeenConverted - Whether or not the module has been converted to
+ * TypeScript.
+ */
+export type ModulePartitionChild = {
+  id: string;
+  hasBeenConverted: boolean;
+  dependentIds: string[];
+  dependencyIds: string[];
+};
+
 /**
  * Represents a set of modules that sit at a certain level within the final
  * dependency tree.
@@ -34,16 +52,10 @@ type Module = {
  * @property level - How many modules it takes to import this module (from the
  * root of the dependency tree).
  * @property children - The modules that share this same level.
- * @property children[].name - The name of the item being imported.
- * @property children[].hasBeenConverted - Whether or not the module (assuming
- * that it is a file in our codebase) has been converted to TypeScript.
  */
 export type ModulePartition = {
   level: number;
-  children: {
+  children: ModulePartitionChild[];
-    name: string;
-    hasBeenConverted: boolean;
-  }[];
 };
 
 /**
@@ -196,10 +208,11 @@ function buildModulesWithLevels(
   // includes `foo.js`, so we say `foo.js` is a circular dependency of `baz.js`,
   // and we don't need to follow it.
 
-  const modulesToFill: Module[] = entryModuleIds.map((moduleId) => {
+  let modulesToFill: Module[] = entryModuleIds.map((moduleId) => {
     return {
       id: moduleId,
       dependents: [],
+      dependencies: [],
       level: 0,
       isExternal: false,
       hasBeenConverted: /\.tsx?$/u.test(moduleId),
@@ -208,56 +221,69 @@ function buildModulesWithLevels(
   const modulesById: Record<string, Module> = {};
 
   while (modulesToFill.length > 0) {
-    const currentModule = modulesToFill.shift() as Module;
+    const currentModule = modulesToFill[0];
-    const childModulesToFill: Module[] = [];
+
-    (dependenciesByModuleId[currentModule.id] ?? []).forEach(
+    if (currentModule.level > 100) {
-      (givenChildModuleId) => {
+      throw new Error(
-        const npmPackageMatch = givenChildModuleId.match(
+        "Can't build module partitions, as the dependency graph is being traversed ad infinitum.",
+      );
+    }
+
+    const dependencyModulesToFill: Module[] = [];
+    for (const nonCanonicalDependencyModuleId of dependenciesByModuleId[
+      currentModule.id
+    ]) {
+      // If the file path of the module is located in `node_modules`, use the
+      // name of the package as the ID
+      let dependencyModuleId;
+      const npmPackageMatch = nonCanonicalDependencyModuleId.match(
         /^node_modules\/(?:(@[^/]+)\/)?([^/]+)\/.+$/u,
       );
-
-        let childModuleId;
       if (npmPackageMatch) {
-          childModuleId =
+        dependencyModuleId =
           npmPackageMatch[1] === undefined
             ? `${npmPackageMatch[2]}`
             : `${npmPackageMatch[1]}/${npmPackageMatch[2]}`;
       } else {
-          childModuleId = givenChildModuleId;
+        dependencyModuleId = nonCanonicalDependencyModuleId;
       }
 
       // Skip circular dependencies
       if (
-          findDirectAndIndirectDependentIdsOf(currentModule).has(childModuleId)
+        findDirectAndIndirectDependentIdsOf(currentModule).has(
+          dependencyModuleId,
+        )
       ) {
-          return;
+        continue;
       }
 
       // Skip files that weren't on the original list of JavaScript files to
       // convert, as we don't want them to show up on the status dashboard
       if (
         !npmPackageMatch &&
-          !allowedFilePaths.includes(childModuleId.replace(/\.tsx?$/u, '.js'))
+        !allowedFilePaths.includes(
+          dependencyModuleId.replace(/\.tsx?$/u, '.js'),
+        )
       ) {
-          return;
+        continue;
       }
 
-        const existingChildModule = modulesById[childModuleId];
+      let existingDependencyModule = modulesById[dependencyModuleId];
 
-        if (existingChildModule === undefined) {
+      if (existingDependencyModule === undefined) {
-          const childModule: Module = {
+        existingDependencyModule = {
-            id: childModuleId,
+          id: dependencyModuleId,
           dependents: [currentModule],
+          dependencies: [],
           level: currentModule.level + 1,
           isExternal: Boolean(npmPackageMatch),
-            hasBeenConverted: /\.tsx?$/u.test(childModuleId),
+          hasBeenConverted: /\.tsx?$/u.test(dependencyModuleId),
         };
-          childModulesToFill.push(childModule);
+        dependencyModulesToFill.push(existingDependencyModule);
-        } else {
+      } else if (currentModule.level + 1 > existingDependencyModule.level) {
-          if (currentModule.level + 1 > existingChildModule.level) {
+        existingDependencyModule.level = currentModule.level + 1;
-            existingChildModule.level = currentModule.level + 1;
         // Update descendant modules' levels
-            childModulesToFill.push(existingChildModule);
+        dependencyModulesToFill.push(existingDependencyModule);
       } else {
         // There is no point in descending into dependencies of this module
         // if the new level of the module would be <= the existing level,
@@ -266,18 +292,30 @@ function buildModulesWithLevels(
         // level.
       }
 
-          if (!existingChildModule.dependents.includes(currentModule)) {
+      if (
-            existingChildModule.dependents.push(currentModule);
+        !existingDependencyModule.dependents.some(
+          (m) => m.id === currentModule.id,
+        )
+      ) {
+        existingDependencyModule.dependents.push(currentModule);
+      }
+
+      if (
+        !currentModule.dependencies.some(
+          (m) => m.id === existingDependencyModule.id,
+        )
+      ) {
+        currentModule.dependencies.push(existingDependencyModule);
       }
     }
-      },
+    if (dependencyModulesToFill.length > 0) {
-    );
+      modulesToFill.push(...dependencyModulesToFill);
-    if (childModulesToFill.length > 0) {
-      modulesToFill.push(...childModulesToFill);
     }
+
     if (!(currentModule.id in modulesById)) {
       modulesById[currentModule.id] = currentModule;
     }
+    modulesToFill = modulesToFill.slice(1);
   }
 
   return modulesById;
@@ -288,20 +326,21 @@ function buildModulesWithLevels(
  * which import that file directly or through some other file.
  *
  * @param module - A module in the graph.
- * @returns The ids of the modules which are incoming connections to
+ * @returns The ids of the modules which are direct and indirect dependents of
  * the module.
  */
 function findDirectAndIndirectDependentIdsOf(module: Module): Set<string> {
-  const modulesToProcess = [module];
+  let modulesToProcess = [module];
   const allDependentIds = new Set<string>();
   while (modulesToProcess.length > 0) {
-    const currentModule = modulesToProcess.shift() as Module;
+    const currentModule = modulesToProcess[0];
-    currentModule.dependents.forEach((dependent) => {
+    for (const dependent of currentModule.dependents) {
       if (!allDependentIds.has(dependent.id)) {
         allDependentIds.add(dependent.id);
         modulesToProcess.push(dependent);
       }
-    });
+    }
+    modulesToProcess = modulesToProcess.slice(1);
   }
   return allDependentIds;
 }
@@ -328,8 +367,22 @@ function partitionModulesByLevel(
   }
   Object.values(modulesById).forEach((module) => {
     modulePartitions[module.level].children.push({
-      name: module.id,
+      id: module.id,
       hasBeenConverted: module.hasBeenConverted,
+      dependentIds: module.dependents.map((dependent) => dependent.id).sort(),
+      dependencyIds: module.dependencies
+        .map((dependency) => dependency.id)
+        .sort(),
+    });
+  });
+  Object.values(modulePartitions).forEach((partition) => {
+    partition.children.sort((a, b) => {
+      if (a.id < b.id) {
+        return -1;
+      } else if (a.id > b.id) {
+        return 1;
+      }
+      return 0;
     });
   });
   return modulePartitions.reverse();