Add DiagsToWarnings function. Closes #474

Author: kaidaguerre

plugin/diags.go

@@ -0,0 +1,58 @@
+package plugin
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/hashicorp/hcl/v2"
+)
+
+// DiagsToError converts tfdiags diags into an error
+func DiagsToError(prefix string, diags hcl.Diagnostics) error {
+	if !diags.HasErrors() {
+		return nil
+	}
+	errStrings := diagsToString(diags, hcl.DiagError)
+
+	var res string
+	if len(errStrings) > 0 {
+		res = strings.Join(errStrings, "\n")
+		if len(errStrings) > 1 {
+			res += "\n"
+		}
+		return fmt.Errorf("%s\n%s", prefix, res)
+	}
+
+	return diags.Errs()[0]
+}
+
+// DiagsToWarning converts warning diags into a list of warning strings
+func DiagsToWarnings(diags hcl.Diagnostics) []string {
+	return diagsToString(diags, hcl.DiagWarning)
+}
+
+func diagsToString(diags hcl.Diagnostics, severity hcl.DiagnosticSeverity) []string { // convert the first diag into an error
+	// store list of messages (without the range) and use for deduping (we may get the same message for multiple ranges)
+	var msgMap = make(map[string]struct{})
+	var strs []string
+	for _, diag := range diags {
+		if diag.Severity == severity {
+			str := fmt.Sprintf("%s", diag.Summary)
+			if diag.Detail != "" {
+				str += fmt.Sprintf(": %s", diag.Detail)
+			}
+
+			if _, ok := msgMap[str]; !ok {
+				msgMap[str] = struct{}{}
+				// now add in the subject and add to the output array
+				if diag.Subject != nil && len(diag.Subject.Filename) > 0 {
+					str += fmt.Sprintf("\n(%s)", diag.Subject.String())
+				}
+
+				strs = append(strs, str)
+			}
+		}
+	}
+
+	return strs
+}