Merge pull request #56 from yassinebenaid/dev

Add support for `&&` and `||` conditional command execution

Author: yassinebenaid

docs/supported-features.md

@@ -39,3 +39,8 @@ key=value key2="value" command
 ```shell
 command | command2 | command3
 ```
+
+## Conditional Execution
+```shell
+command || command2 && command3
+```

generator/generator.go

@@ -44,9 +44,60 @@ func (g *generator) generate(buf *InstructionBuffer, statement ast.Statement, pc
 		*buf = append(*buf, ir.Closure{
 			Body: cmdbuf,
 		})
+	case ast.List:
+		g.handleList(buf, v)
 	}
 }
 
+func (g *generator) handleList(buf *InstructionBuffer, l ast.List) {
+	g.generate(buf, l.Left, nil)
+
+	var bodybuf InstructionBuffer
+	g.generate(&bodybuf, l.Right, nil)
+
+	buf.add(ir.IfLastExitCode{
+		Zero: l.Operator == "&&",
+		Body: bodybuf,
+	})
+}
+
+func (g *generator) handlePipeline(buf *InstructionBuffer, p ast.Pipeline) {
+	buf.add(ir.NewPipelineWaitgroup("pipelineWaitgroup"))
+
+	for i, cmd := range p {
+		if i < (len(p) - 1) { //last command doesn't need a pipe
+			buf.add(ir.NewPipe{
+				Writer: fmt.Sprintf("pipeWriter%d", i+1),
+				Reader: fmt.Sprintf("pipeReader%d", i+1),
+			})
+		}
+
+		var pc pipeContext
+		if i == 0 {
+			pc = pipeContext{
+				writer: fmt.Sprintf("pipeWriter%d", i+1),
+				stderr: cmd.Stderr,
+			}
+		} else if i == (len(p) - 1) {
+			pc = pipeContext{
+				reader: fmt.Sprintf("pipeReader%d", i),
+			}
+		} else {
+			pc = pipeContext{
+				writer: fmt.Sprintf("pipeWriter%d", i+1),
+				reader: fmt.Sprintf("pipeReader%d", i),
+				stderr: cmd.Stderr,
+			}
+		}
+
+		pc.waitgroup = "pipelineWaitgroup"
+		g.generate(buf, cmd.Command, &pc)
+	}
+
+	buf.add(ir.WaitPipelineWaitgroup("pipelineWaitgroup"))
+
+}
+
 func (g *generator) handleSimpleCommand(buf *InstructionBuffer, cmd ast.Command, pc *pipeContext) {
 	buf.add(ir.Declare{Name: "commandName", Value: g.handleExpression(cmd.Name)})
 	buf.add(ir.DeclareSlice{Name: "arguments"})
@@ -258,40 +309,3 @@ type pipeContext struct {
 	waitgroup string
 	stderr    bool
 }
-
-func (g *generator) handlePipeline(buf *InstructionBuffer, p ast.Pipeline) {
-	buf.add(ir.NewPipelineWaitgroup("pipelineWaitgroup"))
-
-	for i, cmd := range p {
-		if i < (len(p) - 1) { //last command doesn't need a pipe
-			buf.add(ir.NewPipe{
-				Writer: fmt.Sprintf("pipeWriter%d", i+1),
-				Reader: fmt.Sprintf("pipeReader%d", i+1),
-			})
-		}
-
-		var pc pipeContext
-		if i == 0 {
-			pc = pipeContext{
-				writer: fmt.Sprintf("pipeWriter%d", i+1),
-				stderr: cmd.Stderr,
-			}
-		} else if i == (len(p) - 1) {
-			pc = pipeContext{
-				reader: fmt.Sprintf("pipeReader%d", i),
-			}
-		} else {
-			pc = pipeContext{
-				writer: fmt.Sprintf("pipeWriter%d", i+1),
-				reader: fmt.Sprintf("pipeReader%d", i),
-				stderr: cmd.Stderr,
-			}
-		}
-
-		pc.waitgroup = "pipelineWaitgroup"
-		g.generate(buf, cmd.Command, &pc)
-	}
-
-	buf.add(ir.WaitPipelineWaitgroup("pipelineWaitgroup"))
-
-}