Merge pull request #76 from yassinebenaid/subshells

Subshells

Author: yassinebenaid

generator/compound.go

@@ -41,3 +41,42 @@ func (g *generator) handleGroup(buf *InstructionBuffer, group ast.Group, pc *pip
 		Body: cmdbuf,
 	})
 }
+
+func (g *generator) handleSubshell(buf *InstructionBuffer, subshell ast.SubShell, pc *pipeContext) {
+	var cmdbuf InstructionBuffer
+
+	cmdbuf.add(ir.CloneShell{})
+
+	g.handleRedirections(&cmdbuf, "subshell", subshell.Redirections, pc, true)
+
+	if pc == nil {
+		for _, cmd := range subshell.Body {
+			g.generate(&cmdbuf, cmd, nil)
+		}
+	} else {
+		cmdbuf.add(ir.Literal("var done = make(chan struct{},1)"))
+		cmdbuf.add(ir.Literal(`
+			pipelineWaitgroup = append(pipelineWaitgroup, runtime.PiplineWaitgroupItem{
+				Wait: func()error{
+					<-done
+					return nil
+				},
+			})
+		`))
+
+		var go_routing InstructionBuffer
+		go_routing.add(ir.Literal("defer streamManager.Destroy()\n"))
+		for _, cmd := range subshell.Body {
+			g.generate(&go_routing, cmd, nil)
+		}
+		go_routing.add(ir.Literal("done<-struct{}{}\n"))
+		cmdbuf.add(ir.Closure{
+			Async: true,
+			Body:  go_routing,
+		})
+	}
+
+	*buf = append(*buf, ir.Closure{
+		Body: cmdbuf,
+	})
+}

generator/generator.go

@@ -20,7 +20,7 @@ func Generate(script ast.Script) ir.Program {
 	}
 }
 
-type generator struct {}
+type generator struct{}
 
 type InstructionBuffer []ir.Instruction
 
@@ -40,6 +40,10 @@ func (g *generator) generate(buf *InstructionBuffer, statement ast.Statement, pc
 		g.handleParameterAssignment(buf, v)
 	case ast.Group:
 		g.handleGroup(buf, v, pc)
+	case ast.SubShell:
+		g.handleSubshell(buf, v, pc)
+	default:
+		panic(fmt.Sprintf("unhandled statement type (%T)", statement))
 	}
 }