Improve error messages, esp. when the server is running

* Add file context to minifier errors when publishing
* Misc fixes (see issues)
* Allow custom server error template in layouts/server/error.html

To get to this, this commit also cleans up and simplifies the code surrounding errors and files. This also removes the usage of `github.com/pkg/errors`, mostly because of https://github.com/pkg/errors/issues/223 -- but also because most of this is now built-in to Go.

Fixes #9852
Fixes #9857
Fixes #9863

resources/page/page_generate/generate_page_wrappers.go

@@ -20,7 +20,7 @@ import (
 	"path/filepath"
 	"reflect"
 
-	"github.com/pkg/errors"
+	"errors"
 
 	"github.com/gohugoio/hugo/common/maps"
 
@@ -55,15 +55,15 @@ var (
 
 func Generate(c *codegen.Inspector) error {
 	if err := generateMarshalJSON(c); err != nil {
-		return errors.Wrap(err, "failed to generate JSON marshaler")
+		return fmt.Errorf("failed to generate JSON marshaler: %w", err)
 	}
 
 	if err := generateDeprecatedWrappers(c); err != nil {
-		return errors.Wrap(err, "failed to generate deprecate wrappers")
+		return fmt.Errorf("failed to generate deprecate wrappers: %w", err)
 	}
 
 	if err := generateFileIsZeroWrappers(c); err != nil {
-		return errors.Wrap(err, "failed to generate file wrappers")
+		return fmt.Errorf("failed to generate file wrappers: %w", err)
 	}
 
 	return nil

resources/page/page_matcher.go

@@ -14,13 +14,13 @@
 package page
 
 import (
+	"fmt"
 	"path/filepath"
 	"strings"
 
 	"github.com/gohugoio/hugo/common/maps"
 	"github.com/gohugoio/hugo/hugofs/glob"
 	"github.com/mitchellh/mapstructure"
-	"github.com/pkg/errors"
 )
 
 // A PageMatcher can be used to match a Page with Glob patterns.
@@ -132,7 +132,7 @@ func DecodePageMatcher(m any, v *PageMatcher) error {
 			}
 		}
 		if !found {
-			return errors.Errorf("%q did not match a valid Page Kind", v.Kind)
+			return fmt.Errorf("%q did not match a valid Page Kind", v.Kind)
 		}
 	}
 

resources/page/pages_related.go

@@ -14,11 +14,11 @@
 package page
 
 import (
+	"fmt"
 	"sync"
 
 	"github.com/gohugoio/hugo/common/types"
 	"github.com/gohugoio/hugo/related"
-	"github.com/pkg/errors"
 	"github.com/spf13/cast"
 )
 
@@ -108,7 +108,7 @@ func (p Pages) withInvertedIndex(search func(idx *related.InvertedIndex) ([]rela
 
 	d, ok := p[0].(InternalDependencies)
 	if !ok {
-		return nil, errors.Errorf("invalid type %T in related search", p[0])
+		return nil, fmt.Errorf("invalid type %T in related search", p[0])
 	}
 
 	cache := d.GetRelatedDocsHandler()

resources/page/permalinks.go

@@ -23,7 +23,7 @@ import (
 	"strings"
 	"time"
 
-	"github.com/pkg/errors"
+	"errors"
 
 	"github.com/gohugoio/hugo/helpers"
 )