all: Refactor to nonglobal Viper, i18n etc.

This is a final rewrite that removes all the global state in Hugo, which also enables
the use if `t.Parallel` in tests.

Updates #2701
Fixes #3016

helpers/pathspec.go

@@ -16,6 +16,7 @@ package helpers
 import (
 	"fmt"
 
+	"github.com/spf13/hugo/config"
 	"github.com/spf13/hugo/hugofs"
 )
 
@@ -26,11 +27,20 @@ type PathSpec struct {
 	uglyURLs           bool
 	canonifyURLs       bool
 
-	currentContentLanguage *Language
+	language *Language
 
 	// pagination path handling
 	paginatePath string
 
+	baseURL string
+	theme   string
+
+	// Directories
+	themesDir  string
+	layoutDir  string
+	workingDir string
+	staticDir  string
+
 	// The PathSpec looks up its config settings in both the current language
 	// and then in the global Viper config.
 	// Some settings, the settings listed below, does not make sense to be set
@@ -45,31 +55,35 @@ type PathSpec struct {
 }
 
 func (p PathSpec) String() string {
-	return fmt.Sprintf("PathSpec, language %q, prefix %q, multilingual: %T", p.currentContentLanguage.Lang, p.getLanguagePrefix(), p.multilingual)
+	return fmt.Sprintf("PathSpec, language %q, prefix %q, multilingual: %T", p.language.Lang, p.getLanguagePrefix(), p.multilingual)
 }
 
-// NewPathSpec creats a new PathSpec from the given filesystems and ConfigProvider.
-func NewPathSpec(fs *hugofs.Fs, config ConfigProvider) *PathSpec {
+// NewPathSpec creats a new PathSpec from the given filesystems and Language.
+func NewPathSpec(fs *hugofs.Fs, cfg config.Provider) *PathSpec {
 
-	currCl, ok := config.Get("currentContentLanguage").(*Language)
-
-	if !ok {
-		// TODO(bep) globals
-		currCl = NewLanguage("en")
-	}
-
-	return &PathSpec{
+	ps := &PathSpec{
 		fs:                             fs,
-		disablePathToLower:             config.GetBool("disablePathToLower"),
-		removePathAccents:              config.GetBool("removePathAccents"),
-		uglyURLs:                       config.GetBool("uglyURLs"),
-		canonifyURLs:                   config.GetBool("canonifyURLs"),
-		multilingual:                   config.GetBool("multilingual"),
-		defaultContentLanguageInSubdir: config.GetBool("defaultContentLanguageInSubdir"),
-		defaultContentLanguage:         config.GetString("defaultContentLanguage"),
-		currentContentLanguage:         currCl,
-		paginatePath:                   config.GetString("paginatePath"),
+		disablePathToLower:             cfg.GetBool("disablePathToLower"),
+		removePathAccents:              cfg.GetBool("removePathAccents"),
+		uglyURLs:                       cfg.GetBool("uglyURLs"),
+		canonifyURLs:                   cfg.GetBool("canonifyURLs"),
+		multilingual:                   cfg.GetBool("multilingual"),
+		defaultContentLanguageInSubdir: cfg.GetBool("defaultContentLanguageInSubdir"),
+		defaultContentLanguage:         cfg.GetString("defaultContentLanguage"),
+		paginatePath:                   cfg.GetString("paginatePath"),
+		baseURL:                        cfg.GetString("baseURL"),
+		themesDir:                      cfg.GetString("themesDir"),
+		layoutDir:                      cfg.GetString("layoutDir"),
+		workingDir:                     cfg.GetString("workingDir"),
+		staticDir:                      cfg.GetString("staticDir"),
+		theme:                          cfg.GetString("theme"),
 	}
+
+	if language, ok := cfg.(*Language); ok {
+		ps.language = language
+	}
+
+	return ps
 }
 
 // PaginatePath returns the configured root path used for paginator pages.