testing: Get to 100% coverage

Also:
- internally renames `isCallingBack` to `isCallback` as per file name and usage
- removed code block from `always-return` which is not necessary given that "good" return/throw statements cannot occur within shortcut syntax (which expect expressions)

Author: brettz9

__tests__/catch-or-return.js

@@ -123,6 +123,9 @@ ruleTester.run('catch-or-return', rule, {
       code: 'frank().then(go).finally()',
       options: [{ terminationMethod: ['catch', 'finally'] }],
     },
+
+    // for coverage
+    'nonPromiseExpressionStatement();',
   ],
 
   invalid: [

__tests__/param-names.js

@@ -17,6 +17,7 @@ ruleTester.run('param-names', rule, {
     'new Promise(resolve => {})',
     'new Promise((resolve, reject) => {})',
     'new Promise(() => {})',
+    'new NonPromise()',
   ],
 
   invalid: [

__tests__/prefer-await-to-callbacks.js

@@ -17,6 +17,7 @@ ruleTester.run('prefer-await-to-callbacks', rule, {
     'async function hi() { await thing().catch() }',
     'dbConn.on("error", err => { console.error(err) })',
     'dbConn.once("error", err => { console.error(err) })',
+    'heart(something => {})',
   ],
 
   invalid: [

__tests__/prefer-await-to-then.js

@@ -20,6 +20,7 @@ ruleTester.run('prefer-await-to-then', rule, {
       try { await something() } catch (error) { somethingElse() }
     }`,
     'something().then(async () => await somethingElse())',
+    'function foo() { hey.somethingElse(x => {}) }',
   ],
 
   invalid: [

package.json

@@ -62,6 +62,14 @@
     "proseWrap": "always"
   },
   "jest": {
+    "coverageThreshold": {
+      "global": {
+        "branches": 100,
+        "functions": 100,
+        "lines": 100,
+        "statements": 100
+      }
+    },
     "projects": [
       {
         "displayName": "test",

rules/always-return.js

@@ -35,6 +35,7 @@ function isInlineThenFunctionExpression(node) {
 }
 
 function hasParentReturnStatement(node) {
+  // istanbul ignore else -- not reachable given not checking `Program`
   if (node && node.parent && node.parent.type) {
     // if the parent is a then, and we haven't returned anything, fail
     if (isThenCallExpression(node.parent)) {
@@ -47,6 +48,7 @@ function hasParentReturnStatement(node) {
     return hasParentReturnStatement(node.parent)
   }
 
+  // istanbul ignore next -- not reachable given not checking `Program`
   return false
 }
 
@@ -139,13 +141,6 @@ module.exports = {
               return
             }
 
-            // check shortcircuit syntax like `x && x()` and `y || x()``
-            const prevSegments = segment.prevSegments
-            for (let ii = prevSegments.length - 1; ii >= 0; --ii) {
-              const prevSegment = prevSegments[ii]
-              if (funcInfo.branchInfoMap[prevSegment.id].good) return
-            }
-
             context.report({
               message: 'Each then() should return a value or throw',
               node: branch.node,

rules/lib/has-promise-callback.js

@@ -7,6 +7,7 @@
 'use strict'
 
 function hasPromiseCallback(node) {
+  // istanbul ignore if -- only being called within `CallExpression`
   if (node.type !== 'CallExpression') return
   if (node.callee.type !== 'MemberExpression') return
   const propertyName = node.callee.property.name

rules/lib/is-callback.js

@@ -2,12 +2,13 @@
 
 const isNamedCallback = require('./is-named-callback')
 
-function isCallingBack(node, exceptions) {
+function isCallback(node, exceptions) {
   const isCallExpression = node.type === 'CallExpression'
+  // istanbul ignore next -- always invoked on `CallExpression`
   const callee = node.callee || {}
   const nameIsCallback = isNamedCallback(callee.name, exceptions)
   const isCB = isCallExpression && nameIsCallback
   return isCB
 }
 
-module.exports = isCallingBack
+module.exports = isCallback

rules/no-native.js

@@ -11,10 +11,14 @@ function isDeclared(scope, ref) {
       return false
     }
 
+    // Presumably can't pass this since the implicit `Promise` global
+    //  being checked here would always lack `defs`
+    // istanbul ignore else
     if (!variable.defs || !variable.defs.length) {
       return false
     }
 
+    // istanbul ignore next
     return true
   })
 }
@@ -46,6 +50,7 @@ module.exports = {
             return
           }
 
+          // istanbul ignore else
           if (!isDeclared(scope, ref)) {
             context.report({
               node: ref.identifier,

rules/no-return-in-finally.js

@@ -19,6 +19,7 @@ module.exports = {
             node.callee.property &&
             node.callee.property.name === 'finally'
           ) {
+            // istanbul ignore else -- passing `isPromise` means should have a body
             if (
               node.arguments &&
               node.arguments[0] &&