chore: refactor pack tests

Uses the real npm object and doesn't mock anything.

PR-URL: #4018
Credit: @wraithgar
Close: #4018
Reviewed-by: @lukekarrys

tap-snapshots/test/lib/commands/pack.js.test.cjs

@@ -0,0 +1,78 @@
+/* IMPORTANT
+ * This snapshot file is auto-generated, but designed for humans.
+ * It should be checked into source control and tracked carefully.
+ * Re-generate by setting TAP_SNAPSHOT=1 and running tests.
+ * Make sure to inspect the output below.  Do not ignore changes!
+ */
+'use strict'
+exports[`test/lib/commands/pack.js TAP dry run > logs pack contents 1`] = `
+Array [
+  undefined,
+  "package: test-package@1.0.0",
+  undefined,
+  "41B package.json",
+  undefined,
+  String(
+    name:          test-package                            
+    version:       1.0.0                                   
+    filename:      test-package-1.0.0.tgz                  
+    package size:  136 B                                   
+    unpacked size: 41 B                                    
+    shasum:        a92a0679a70a450f14f98a468756948a679e4107
+    integrity:     sha512-Gka9ZV/Bryxky[...]LgMJ+0F+FhXMA==
+    total files:   1                                       
+  ),
+  "",
+]
+`
+
+exports[`test/lib/commands/pack.js TAP should log output as valid json > logs pack contents 1`] = `
+Array []
+`
+
+exports[`test/lib/commands/pack.js TAP should log output as valid json > outputs as json 1`] = `
+Array [
+  Array [
+    Object {
+      "bundled": Array [],
+      "entryCount": 1,
+      "filename": "test-package-1.0.0.tgz",
+      "files": Array [
+        Object {
+          "mode": 420,
+          "path": "package.json",
+          "size": 41,
+        },
+      ],
+      "id": "test-package@1.0.0",
+      "integrity": "sha512-Gka9ZV/BryxkypfvMpTvLfaJE1AUi7PK1EAbYqnVzqtucf6QvUK4CFsLVzagY1GwZVx2T1jwWLgMJ+0F+FhXMA==",
+      "name": "test-package",
+      "shasum": "a92a0679a70a450f14f98a468756948a679e4107",
+      "size": 136,
+      "unpackedSize": 41,
+      "version": "1.0.0",
+    },
+  ],
+]
+`
+
+exports[`test/lib/commands/pack.js TAP should pack current directory with no arguments > logs pack contents 1`] = `
+Array [
+  undefined,
+  "package: test-package@1.0.0",
+  undefined,
+  "41B package.json",
+  undefined,
+  String(
+    name:          test-package                            
+    version:       1.0.0                                   
+    filename:      test-package-1.0.0.tgz                  
+    package size:  136 B                                   
+    unpacked size: 41 B                                    
+    shasum:        a92a0679a70a450f14f98a468756948a679e4107
+    integrity:     sha512-Gka9ZV/Bryxky[...]LgMJ+0F+FhXMA==
+    total files:   1                                       
+  ),
+  "",
+]
+`

test/fixtures/mock-npm.js

@@ -25,6 +25,7 @@ const RealMockNpm = (t, otherMocks = {}) => {
   mock.joinedOutput = () => {
     return mock.outputs.map(o => o.join(' ')).join('\n')
   }
+  mock.filteredLogs = title => mock.logs.filter(([t]) => t === title).map(([, , msg]) => msg)
   const Npm = t.mock('../../lib/npm.js', otherMocks)
   class MockNpm extends Npm {
     constructor () {