Better constraint matching

go.mod

@@ -4,6 +4,7 @@ go 1.21.4
 
 require (
 	github.com/fatih/color v1.16.0
+	github.com/hashicorp/go-version v1.6.0
 	github.com/spf13/cobra v1.8.0
 	golang.org/x/net v0.21.0
 )

go.sum

@@ -1,6 +1,8 @@
 github.com/cpuguy83/go-md2man/v2 v2.0.3/go.mod h1:tgQtvFlXSQOSOSIRvRPT7W67SCa46tRHOmNcaadrF8o=
 github.com/fatih/color v1.16.0 h1:zmkK9Ngbjj+K0yRhTVONQh1p/HknKYSlNT+vZCzyokM=
 github.com/fatih/color v1.16.0/go.mod h1:fL2Sau1YI5c0pdGEVCbKQbLXB6edEj1ZgiY4NijnWvE=
+github.com/hashicorp/go-version v1.6.0 h1:feTTfFNnjP967rlCxM/I9g701jU+RN74YKx2mOkIeek=
+github.com/hashicorp/go-version v1.6.0/go.mod h1:fltr4n8CU8Ke44wwGCBoEymUuxUHl09ZGVZPK5anwXA=
 github.com/inconshreveable/mousetrap v1.1.0 h1:wN+x4NVGpMsO7ErUn/mUI3vEoE6Jt13X2s0bqwp9tc8=
 github.com/inconshreveable/mousetrap v1.1.0/go.mod h1:vpF70FUmC8bwa3OWnCshd2FqLfsEA9PFc4w1p2J65bw=
 github.com/mattn/go-colorable v0.1.13 h1:fFA4WZxdEF4tXPZVKMLwD8oUnCTTo08duU7wxecdEvA=

pkg/helpers/helper.go

@@ -6,6 +6,8 @@ import (
 	"path/filepath"
 	"regexp"
 	"strings"
+
+	"github.com/hashicorp/go-version"
 )
 
 // IsPreReleaseVersion checks if the given version is a Terraform pre-release version
@@ -15,18 +17,28 @@ func IsPreReleaseVersion(version string) bool {
 
 // FindRequiredVersionInFile finds the required Terraform version in a given .tf file (using required_version = ">= x.x.x")
 // TODO: improve logic by using go-version/constraint?
-func FindRequiredVersionInFile(filepath string) string {
+func FindRequiredVersionInFile(filepath string, availableVersions []string) string {
 	bytes, err := os.ReadFile(filepath)
 	if err != nil {
 		fmt.Printf("Unable to find version number in file: %s", filepath)
 		return ""
 	}
-	re := regexp.MustCompile(`required_version\s*=\s*">=? ?(\d+\.\d+\.\d+)"`)
+
+	re := regexp.MustCompile(`required_version\s?=\s?"([^"]+)"`)
 	match := re.FindStringSubmatch(string(bytes))
 	if len(match) == 0 {
 		return ""
 	}
-	return match[1]
+
+	for _, v := range availableVersions {
+		testVersion, _ := version.NewVersion(v)
+		constraints, _ := version.NewConstraint(match[1])
+		if constraints.Check(testVersion) {
+			return v
+		}
+	}
+
+	return ""
 }
 
 // FindTerraformFiles finds all .tf files in the current directory (module)

pkg/install/install.go

@@ -55,20 +55,21 @@ func InstallLatestVersion(preRelease bool) {
 func InstallRequiredVersion() {
 	terraformFiles := helpers.FindTerraformFiles()
 	if len(terraformFiles) == 0 {
-		fmt.Println("No Terraform files found in current directory")
+		fmt.Println("error: no Terraform files found in current directory")
 		os.Exit(1)
 	}
 
 	var foundVersion string
+	availableVersions := list.GetAvailableVersions()
 	for _, file := range terraformFiles {
-		requiredVersion := helpers.FindRequiredVersionInFile(file)
+		requiredVersion := helpers.FindRequiredVersionInFile(file, availableVersions)
 		if requiredVersion != "" {
 			foundVersion = requiredVersion
 		}
 	}
 
 	if len(foundVersion) == 0 {
-		fmt.Println("No required version found in current directory")
+		fmt.Println("error: no required version found in current directory")
 		os.Exit(1)
 	}
 

pkg/use/use.go

@@ -82,8 +82,10 @@ func UseRequiredVersion() {
 		fmt.Println("No Terraform files found in current directory")
 		os.Exit(1)
 	}
+
+	availableVersions := list.GetAvailableVersions()
 	for _, file := range terraformFiles {
-		requiredVersion := helpers.FindRequiredVersionInFile(file)
+		requiredVersion := helpers.FindRequiredVersionInFile(file, availableVersions)
 		if requiredVersion != "" {
 			UseVersion(requiredVersion)
 			break