cli: Add MVP implementation for SCIP view command. (#91)

Author: varungandhi-src

Development.md

@@ -37,7 +37,14 @@
 
 ## Debugging
 
-Protobuf output can be inspected using `protoc`:
+Protobuf output can be inspected using `scip view`:
+
+```
+scip print /path/to/index.scip
+```
+
+This may be a bit verbose. The default Protobuf output is more compact,
+and can be inspected using `protoc`:
 
 ```
 protoc --decode=scip.Index -I /path/to/scip scip.proto < index.scip

Readme.md

@@ -90,6 +90,23 @@ OPTIONS:
    --to value    Output path for LSIF index (default: dump.lsif)
 ```
 
+### `scip print`
+
+```
+NAME:
+   scip print - Print a SCIP index in a human-readable format for debugging
+
+USAGE:
+   scip print [command options] [arguments...]
+
+DESCRIPTION:
+   WARNING: The output may change over time.
+   Do not rely on the output of this command in scripts
+
+OPTIONS:
+   --help, -h  show help (default: false)
+```
+
 ### `scip snapshot`
 
 ```

cmd/main.go

@@ -19,7 +19,8 @@ func commands() []*cli.Command {
 	convert := convertCommand()
 	snapshot := snapshotCommand()
 	stats := statsCommand()
-	return []*cli.Command{&convert, &snapshot, &stats}
+	print := printCommand()
+	return []*cli.Command{&convert, &snapshot, &stats, &print}
 }
 
 func scipApp() cli.App {
@@ -54,6 +55,6 @@ func fromFlag(storage *string) *cli.StringFlag {
 		Name:        "from",
 		Usage:       "Path to SCIP index file",
 		Destination: storage,
-		Value: "index.scip",
+		Value:       "index.scip",
 	}
 }

cmd/print.go

@@ -0,0 +1,38 @@
+package main
+
+import (
+	"github.com/k0kubun/pp/v3"
+	"github.com/urfave/cli/v2"
+	"math"
+
+	"github.com/sourcegraph/sourcegraph/lib/errors"
+)
+
+func printCommand() cli.Command {
+	snapshot := cli.Command{
+		Name:  "print",
+		Usage: "Print a SCIP index in a human-readable format for debugging",
+		Description: `WARNING: The output may change over time.
+Do not rely on the output of this command in scripts`,
+		Action: func(c *cli.Context) error {
+			indexPath := c.Args().Get(0)
+			if indexPath == "" {
+				return errors.New("missing argument for path to SCIP index")
+			}
+			return printMain(indexPath)
+		},
+	}
+	return snapshot
+}
+
+func printMain(indexPath string) error {
+	index, err := readFromOption(indexPath)
+	if err != nil {
+		return err
+	}
+	pp.BufferFoldThreshold = math.MaxInt
+	prettyPrinter := pp.New()
+	prettyPrinter.SetExportedOnly(true)
+	_, err = prettyPrinter.Print(index)
+	return err
+}

go.mod

@@ -7,6 +7,7 @@ require (
 	github.com/google/go-cmp v0.5.7
 	github.com/hexops/gotextdiff v1.0.3
 	github.com/hhatto/gocloc v0.4.2
+	github.com/k0kubun/pp/v3 v3.1.0
 	github.com/pseudomuto/protoc-gen-doc v1.5.1
 	github.com/smacker/go-tree-sitter v0.0.0-20220209044044-0d3022e933c3
 	github.com/sourcegraph/sourcegraph/lib v0.0.0-20220511160847-5a43d3ea24eb
@@ -46,6 +47,8 @@ require (
 	github.com/klauspost/pgzip v1.2.5 // indirect
 	github.com/kr/pretty v0.3.0 // indirect
 	github.com/kr/text v0.2.0 // indirect
+	github.com/mattn/go-colorable v0.1.12 // indirect
+	github.com/mattn/go-isatty v0.0.14 // indirect
 	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
 	github.com/modern-go/reflect2 v1.0.2 // indirect
 	github.com/mwitkow/go-proto-validators v0.0.0-20180403085117-0950a7990007 // indirect

go.sum

@@ -185,6 +185,8 @@ github.com/juju/errors v0.0.0-20181118221551-089d3ea4e4d5/go.mod h1:W54LbzXuIE0b
 github.com/juju/loggo v0.0.0-20180524022052-584905176618/go.mod h1:vgyd7OREkbtVEN/8IXZe5Ooef3LQePvuBm9UWj6ZL8U=
 github.com/juju/testing v0.0.0-20180920084828-472a3e8b2073/go.mod h1:63prj8cnj0tU0S9OHjGJn+b1h0ZghCndfnbQolrYTwA=
 github.com/k0kubun/colorstring v0.0.0-20150214042306-9440f1994b88/go.mod h1:3w7q1U84EfirKl04SVQ/s7nPm1ZPhiXd34z40TNz36k=
+github.com/k0kubun/pp/v3 v3.1.0 h1:ifxtqJkRZhw3h554/z/8zm6AAbyO4LLKDlA5eV+9O8Q=
+github.com/k0kubun/pp/v3 v3.1.0/go.mod h1:vIrP5CF0n78pKHm2Ku6GVerpZBJvscg48WepUYEk2gw=
 github.com/kataras/golog v0.0.9/go.mod h1:12HJgwBIZFNGL0EJnMRhmvGA0PQGx8VFwrZtM4CqbAk=
 github.com/kataras/golog v0.0.10/go.mod h1:yJ8YKCmyL+nWjERB90Qwn+bdyBZsaQwU3bTVFgkFIp8=
 github.com/kataras/iris/v12 v12.0.1/go.mod h1:udK4vLQKkdDqMGJJVd/msuMtN6hpYJhg/lSzuxjhO+U=
@@ -219,10 +221,13 @@ github.com/magiconair/properties v1.8.0/go.mod h1:PppfXfuXeibc/6YijjN8zIbojt8czP
 github.com/mattn/go-colorable v0.1.2/go.mod h1:U0ppj6V5qS13XJ6of8GYAs25YV2eR4EVcfRqFIhoBtE=
 github.com/mattn/go-colorable v0.1.8/go.mod h1:u6P/XSegPjTcexA+o6vUJrdnUu04hMope9wVRipJSqc=
 github.com/mattn/go-colorable v0.1.11/go.mod h1:u5H1YNBxpqRaxsYJYSkiCWKzEfiAb1Gb520KVy5xxl4=
+github.com/mattn/go-colorable v0.1.12 h1:jF+Du6AlPIjs2BiUiQlKOX0rt3SujHxPnksPKZbaA40=
+github.com/mattn/go-colorable v0.1.12/go.mod h1:u5H1YNBxpqRaxsYJYSkiCWKzEfiAb1Gb520KVy5xxl4=
 github.com/mattn/go-isatty v0.0.7/go.mod h1:Iq45c/XA43vh69/j3iqttzPXn0bhXyGjM0Hdxcsrc5s=
 github.com/mattn/go-isatty v0.0.8/go.mod h1:Iq45c/XA43vh69/j3iqttzPXn0bhXyGjM0Hdxcsrc5s=
 github.com/mattn/go-isatty v0.0.9/go.mod h1:YNRxwqDuOph6SZLI9vUUz6OYw3QyUt7WiY2yME+cCiQ=
 github.com/mattn/go-isatty v0.0.12/go.mod h1:cbi8OIDigv2wuxKPP5vlRcQ1OAZbq2CE4Kysco4FUpU=
+github.com/mattn/go-isatty v0.0.14 h1:yVuAays6BHfxijgZPzw+3Zlu5yQgKGP2/hcQbHb7S9Y=
 github.com/mattn/go-isatty v0.0.14/go.mod h1:7GGIvUiUoEMVVmxf/4nioHXj79iQHKdU27kJ6hsGG94=
 github.com/mattn/goveralls v0.0.2/go.mod h1:8d1ZMHsd7fW6IRPKQh46F2WRpyib5/X4FOpevwGNQEw=
 github.com/mediocregopher/mediocre-go-lib v0.0.0-20181029021733-cb65787f37ed/go.mod h1:dSsfyI2zABAdhcbvkXqgxOxrCsbYeHCPgrZkku60dSg=