fix: apply source-maps to test errors

When we got rid of ts-node in #602, we also unintentionally dropped
the code modifying error stack traces to point to original TypeScript
sources instead of the transpiled JavaScript output.

As a result, assertion failures contained stack traces pointing to code
that we are not familiar with, which made troubleshooing difficult.

This commits add source-map-support as a global dev-dependency
plus a dev-dependency of example repositories that must work outside
of our monorepo too.

The single shared `mocha.opts` was split into two different options
files:

 - `mocha.ts.opts` which registers source-map support
 - `mocha.js.opts` with no support for source maps

Author: bajtos

package.json

@@ -9,7 +9,6 @@
     "node": ">=6"
   },
   "license": "MIT",
-  "dependencies": {},
   "devDependencies": {
     "@commitlint/cli": "^6.0.2",
     "@commitlint/config-conventional": "^6.0.2",
@@ -19,7 +18,8 @@
     "coveralls": "^3.0.0",
     "cz-conventional-changelog": "^2.1.0",
     "lerna": "^2.5.1",
-    "mocha": "^5.0.0"
+    "mocha": "^5.0.0",
+    "source-map-support": "^0.5.2"
   },
   "scripts": {
     "bootstrap": "npm i && lerna bootstrap",
@@ -41,7 +41,7 @@
     "build:full": "npm run clean:full && npm run bootstrap && npm run build && npm run mocha && npm run lint",
     "pretest": "npm run clean && npm run build:current",
     "test": "node packages/build/bin/run-nyc npm run mocha",
-    "mocha": "node packages/build/bin/select-dist mocha --opts packages/build/mocha.opts \"packages/*/DIST/test/**/*.js\" \"packages/cli/test\"",
+    "mocha": "node packages/build/bin/select-dist mocha --opts packages/build/mocha.ts.opts \"packages/*/DIST/test/**/*.js\" \"packages/cli/test\"",
     "posttest": "npm run lint"
   },
   "config": {

packages/authentication/package.json

@@ -6,18 +6,18 @@
     "node": ">=6"
   },
   "scripts": {
-    "acceptance": "lb-dist mocha --opts node_modules/@loopback/build/mocha.opts 'DIST/test/acceptance/**/*.js'",
+    "acceptance": "lb-dist mocha --opts node_modules/@loopback/build/mocha.ts.opts 'DIST/test/acceptance/**/*.js'",
     "build": "npm run build:dist && npm run build:dist6",
     "build:current": "lb-tsc",
     "build:dist": "lb-tsc es2017",
     "build:dist6": "lb-tsc es2015",
     "build:apidocs": "lb-apidocs",
     "clean": "lb-clean loopback-authentication*.tgz dist dist6 package api-docs",
-    "integration": "lb-dist mocha --opts node_modules/@loopback/build/mocha.opts 'DIST/test/integration/**/*.js'",
+    "integration": "lb-dist mocha --opts node_modules/@loopback/build/mocha.ts.opts 'DIST/test/integration/**/*.js'",
     "prepare": "npm run build && npm run build:apidocs",
     "pretest": "npm run build:current",
-    "test": "lb-dist mocha --opts node_modules/@loopback/build/mocha.opts 'DIST/test/unit/**/*.js' 'DIST/test/integration/**/*.js' 'DIST/test/acceptance/**/*.js'",
-    "unit": "lb-dist mocha --opts node_modules/@loopback/build/mocha.opts 'DIST/test/unit/**/*.js'",
+    "test": "lb-dist mocha --opts node_modules/@loopback/build/mocha.ts.opts 'DIST/test/unit/**/*.js' 'DIST/test/integration/**/*.js' 'DIST/test/acceptance/**/*.js'",
+    "unit": "lb-dist mocha --opts node_modules/@loopback/build/mocha.ts.opts 'DIST/test/unit/**/*.js'",
     "verify": "npm pack && tar xf loopback-authentication*.tgz && tree package && npm run clean"
   },
   "author": "IBM",

packages/build/mocha.opts packages/build/mocha.js.optspackages/build/mocha.opts renamed to packages/build/mocha.js.opts

@@ -0,0 +1,4 @@
+--recursive
+--exit
+--reporter dot
+--require source-map-support/register

packages/build/mocha.ts.opts

@@ -40,7 +40,7 @@
     "prettier:check": "npm run prettier:cli -- -l",
     "prettier:fix": "npm run prettier:cli -- --write",
     "test": "npm run mocha",
-    "mocha": "node bin/select-dist mocha --timeout 30000 --opts mocha.opts \"test/integration/*.js\"",
+    "mocha": "node bin/select-dist mocha --opts mocha.js.opts --timeout 30000 \"test/integration/*.js\"",
     "posttest": "npm run lint"
   },
   "devDependencies": {

packages/build/package.json

@@ -72,7 +72,8 @@
 <% if (project.mocha) { -%>
     "@loopback/testlab": ">=4.0.0-alpha.13",
     "@types/mocha": "^2.2.43",
-    "mocha": "^4.0.1"
+    "mocha": "^4.0.1",
+    "source-map-support": "^0.5.2"
 <% } else { -%>
     "@loopback/testlab": ">=4.0.0-alpha.13"
 <% } -%>

packages/cli/generators/project/templates/package.json

@@ -77,6 +77,7 @@
 <% if (project.mocha) { -%>
     "@types/mocha": "^2.2.43",
     "mocha": "^4.0.1",
+    "source-map-support": "^0.5.2",
 <% } -%>
     "typescript": "^2.5.3"
   }

packages/cli/generators/project/templates/package.plain.json

@@ -1 +1,2 @@
 --recursive
+--require source-map-support/register

packages/cli/generators/project/templates/test/mocha.opts

@@ -54,7 +54,7 @@
   },
   "scripts": {
     "prepublishOnly": "nsp check",
-    "test": "mocha test/**/*.js"
+    "test": "mocha --opts node_modules/@loopback/build/mocha.js.opts test/**/*.js"
   },
   "repository": {
     "type": "git",

packages/cli/package.json

@@ -6,7 +6,7 @@
     "node": ">=6"
   },
   "scripts": {
-    "acceptance": "lb-dist mocha --opts node_modules/@loopback/build/mocha.opts 'DIST/test/acceptance/**/*.js'",
+    "acceptance": "lb-dist mocha --opts node_modules/@loopback/build/mocha.ts.opts 'DIST/test/acceptance/**/*.js'",
     "build": "npm run build:dist && npm run build:dist6",
     "build:current": "lb-tsc",
     "build:dist": "lb-tsc es2017",
@@ -15,8 +15,8 @@
     "clean": "lb-clean loopback-context*.tgz dist dist6 package api-docs",
     "prepare": "npm run build && npm run build:apidocs",
     "pretest": "npm run build:current",
-    "test": "lb-dist mocha --opts node_modules/@loopback/build/mocha.opts 'DIST/test/unit/**/*.js' 'DIST/test/acceptance/**/*.js'",
-    "unit": "lb-dist mocha --opts node_modules/@loopback/build/mocha.opts 'DIST/test/unit/**/*.js'",
+    "test": "lb-dist mocha --opts node_modules/@loopback/build/mocha.ts.opts 'DIST/test/unit/**/*.js' 'DIST/test/acceptance/**/*.js'",
+    "unit": "lb-dist mocha --opts node_modules/@loopback/build/mocha.ts.opts 'DIST/test/unit/**/*.js'",
     "verify": "npm pack && tar xf loopback-context*.tgz && tree package && npm run clean"
   },
   "author": "IBM",