Add a --ignore_unknown flag to query whatinputs (#3057)

src/please.go

@@ -403,9 +403,10 @@ var opts struct {
 			} `positional-args:"true"`
 		} `command:"graph" description:"Prints a representation of the build graph."`
 		WhatInputs struct {
-			Hidden    bool `long:"hidden" short:"h" description:"Output internal / hidden targets too."`
-			EchoFiles bool `long:"echo_files" description:"Echo the file for which the printed output is responsible."`
-			Args      struct {
+			Hidden        bool `long:"hidden" short:"h" description:"Output internal / hidden targets too."`
+			EchoFiles     bool `long:"echo_files" description:"Echo the file for which the printed output is responsible."`
+			IgnoreUnknown bool `long:"ignore_unknown" description:"Ignore any files that are not inputs to existing build targets"`
+			Args          struct {
 				Files cli.StdinStrings `positional-arg-name:"files" description:"Files to query as sources to targets" required:"true"`
 			} `positional-args:"true" required:"true"`
 		} `command:"whatinputs" description:"Prints out target(s) with provided file(s) as inputs"`
@@ -883,7 +884,7 @@ var buildFunctions = map[string]func() int{
 			labels = append(labels, core.FindOwningPackage(state, file))
 		}
 		return runQuery(true, labels, func(state *core.BuildState) {
-			query.WhatInputs(state.Graph, files, opts.Query.WhatInputs.Hidden, opts.Query.WhatInputs.EchoFiles)
+			query.WhatInputs(state.Graph, files, opts.Query.WhatInputs.Hidden, opts.Query.WhatInputs.EchoFiles, opts.Query.WhatInputs.IgnoreUnknown)
 		})
 	},
 	"query.whatoutputs": func() int {

src/query/whatinputs.go

@@ -10,7 +10,7 @@ import (
 // WhatInputs prints the targets with the provided files as sources
 // The targets are printed in the same order as the provided files, separated by a newline
 // Use printFiles to additionally echo the files themselves (i.e. print <file> <target>)
-func WhatInputs(graph *core.BuildGraph, files []string, hidden, printFiles bool) {
+func WhatInputs(graph *core.BuildGraph, files []string, hidden, printFiles, ignoreUnknown bool) {
 	targets := graph.AllTargets()
 
 	for _, file := range files {
@@ -21,7 +21,7 @@ func WhatInputs(graph *core.BuildGraph, files []string, hidden, printFiles bool)
 				}
 				fmt.Printf("%s\n", label)
 			}
-		} else {
+		} else if !ignoreUnknown {
 			log.Fatalf("%s is not a source to any current target", file)
 		}
 	}