Remove go1.12 support (#2679)

* Revert "Adding ppc64le architecture support on travis-ci (#2538)"

This reverts commit fca3f95.

* not support go1.12

* fix

* Update errors_test.go

* Update debug.go

.travis.yml

@@ -3,8 +3,6 @@ language: go
 matrix:
   fast_finish: true
   include:
-  - go: 1.12.x
-    env: GO111MODULE=on
   - go: 1.13.x
   - go: 1.13.x
     env:

README.md

@@ -84,7 +84,7 @@ Gin is a web framework written in Go (Golang). It features a martini-like API wi
 
 To install Gin package, you need to install Go and set your Go workspace first.
 
-1. The first need [Go](https://golang.org/) installed (**version 1.12+ is required**), then you can use the below Go command to install Gin.
+1. The first need [Go](https://golang.org/) installed (**version 1.13+ is required**), then you can use the below Go command to install Gin.
 
 ```sh
 $ go get -u github.com/gin-gonic/gin

debug.go

@@ -12,7 +12,7 @@ import (
 	"strings"
 )
 
-const ginSupportMinGoVer = 12
+const ginSupportMinGoVer = 13
 
 // IsDebugging returns true if the framework is running in debug mode.
 // Use SetMode(gin.ReleaseMode) to disable debug mode.
@@ -67,7 +67,7 @@ func getMinVer(v string) (uint64, error) {
 
 func debugPrintWARNINGDefault() {
 	if v, e := getMinVer(runtime.Version()); e == nil && v <= ginSupportMinGoVer {
-		debugPrint(`[WARNING] Now Gin requires Go 1.12+.
+		debugPrint(`[WARNING] Now Gin requires Go 1.13+.
 
 `)
 	}

debug_test.go

@@ -104,7 +104,7 @@ func TestDebugPrintWARNINGDefault(t *testing.T) {
 	})
 	m, e := getMinVer(runtime.Version())
 	if e == nil && m <= ginSupportMinGoVer {
-		assert.Equal(t, "[GIN-debug] [WARNING] Now Gin requires Go 1.12+.\n\n[GIN-debug] [WARNING] Creating an Engine instance with the Logger and Recovery middleware already attached.\n\n", re)
+		assert.Equal(t, "[GIN-debug] [WARNING] Now Gin requires Go 1.13+.\n\n[GIN-debug] [WARNING] Creating an Engine instance with the Logger and Recovery middleware already attached.\n\n", re)
 	} else {
 		assert.Equal(t, "[GIN-debug] [WARNING] Creating an Engine instance with the Logger and Recovery middleware already attached.\n\n", re)
 	}

errors_test.go

@@ -6,6 +6,7 @@ package gin
 
 import (
 	"errors"
+	"fmt"
 	"testing"
 
 	"github.com/gin-gonic/gin/internal/json"
@@ -104,3 +105,24 @@ Error #03: third
 	assert.Nil(t, errs.JSON())
 	assert.Empty(t, errs.String())
 }
+
+type TestErr string
+
+func (e TestErr) Error() string { return string(e) }
+
+// TestErrorUnwrap tests the behavior of gin.Error with "errors.Is()" and "errors.As()".
+// "errors.Is()" and "errors.As()" have been added to the standard library in go 1.13.
+func TestErrorUnwrap(t *testing.T) {
+	innerErr := TestErr("somme error")
+
+	// 2 layers of wrapping : use 'fmt.Errorf("%w")' to wrap a gin.Error{}, which itself wraps innerErr
+	err := fmt.Errorf("wrapped: %w", &Error{
+		Err:  innerErr,
+		Type: ErrorTypeAny,
+	})
+
+	// check that 'errors.Is()' and 'errors.As()' behave as expected :
+	assert.True(t, errors.Is(err, innerErr))
+	var testErr TestErr
+	assert.True(t, errors.As(err, &testErr))
+}